Discussions on the subreddit largely focus on Christianity and Islam and also on the social and cultural dimensions of religion. So I compiled a fairly comprehensive list of this area which gets less attention. Maybe we can spin off some more detailed conversations on these topics on the fediverse.

General

https://reddit.adminforge.de/r/DebateReligion/comments/56zkbi/my_response_to_a_question_regarding_zen_buddhism/

https://reddit.adminforge.de/r/DebateReligion/comments/85t5o8/lovingkindness_attitudebased_buddhist_morality/

https://reddit.adminforge.de/r/DebateReligion/comments/327gx5/siddhartha_gautama_buddha_got_it_right/

https://reddit.adminforge.de/r/DebateReligion/comments/jl7cg0/why_i_believe_mainstream_buddhism_is_illogical/

https://reddit.adminforge.de/r/DebateReligion/comments/2p9urm/looking_for_a_substantive_critique_of_buddhist/

https://reddit.adminforge.de/r/DebateReligion/comments/3e0k6p/a_debate_about_buddhism/

https://reddit.adminforge.de/r/DebateReligion/comments/2f2qqh/challenge_criticise_buddhism/

https://reddit.adminforge.de/r/DebateReligion/comments/36ea4p/criticise_buddhism/

https://reddit.adminforge.de/r/DebateReligion/comments/20jv65/to_all_what_do_you_likenot_like_about_buddhism/

https://reddit.adminforge.de/r/DebateReligion/comments/1de6mb/clash_of_the_dharmas_a_debate_between_hinduism/

https://reddit.adminforge.de/r/DebateReligion/comments/1vqhx3/to_buddhists_can_the_noble_eightfold_paths/

Duhkha, upadana

https://reddit.adminforge.de/r/DebateReligion/comments/13sri99/buddhism_unfairly_characterises_life_as_dominated/

https://reddit.adminforge.de/r/DebateReligion/comments/cd3er9/following_the_eightfold_path_of_buddhism_will/

https://reddit.adminforge.de/r/DebateReligion/comments/dqso8r/the_goal_of_buddhism_is_undesirable_and_buddhists/

https://reddit.adminforge.de/r/DebateReligion/comments/2rmwai/buddhists_about_the_four_noble_truths/

https://reddit.adminforge.de/r/DebateReligion/comments/lq8deo/a_concise_refutation_of_buddhism_in_favour_of/

https://reddit.adminforge.de/r/DebateReligion/comments/13sri99/buddhism_unfairly_characterises_life_as_dominated/

https://reddit.adminforge.de/r/DebateReligion/comments/k2to6/to_buddhists_does_buddhism_present_a_pessimistic/

https://reddit.adminforge.de/r/DebateReligion/comments/o8shu/im_a_buddhist_lets_go/

https://reddit.adminforge.de/r/DebateReligion/comments/1r40bk/to_buddhists_and_everyone_else_if_you_could_have/

https://reddit.adminforge.de/r/DebateReligion/comments/16vhx0/to_nihilists_zen_buddhists_and_stoics_how_do_you/

https://reddit.adminforge.de/r/DebateReligion/comments/170560/to_buddhists_why_do_you_feel_existence_is_always/

God(s), (a)theism, worship

https://reddit.adminforge.de/r/DebateReligion/comments/nh08to/buddha_is_treated_as_a_god_by_buddhists/

https://reddit.adminforge.de/r/DebateReligion/comments/3iutzh/is_buddhism_atheistic/

https://reddit.adminforge.de/r/DebateReligion/comments/6h05hm/how_does_chinese_buddhism_justify_praying_to/

https://reddit.adminforge.de/r/DebateReligion/comments/934ukk/why_buddhism_is_nontheistic_and_how_buddhist/

https://reddit.adminforge.de/r/DebateReligion/comments/79zbz2/is_buddhism_an_atheistic_religion/

https://reddit.adminforge.de/r/DebateReligion/comments/1txka0/to_abrahamic_theists_would_you_consider_buddhism/

https://reddit.adminforge.de/r/DebateReligion/comments/3ec06k/are_almostgods_implied_by_buddhism/

https://reddit.adminforge.de/r/DebateReligion/comments/1egk5f/to_athiestsbuddhists_i_have_heard_buddhism/

https://reddit.adminforge.de/r/DebateReligion/comments/aclc59/buddhists_and_confucians_who_present_their/

https://reddit.adminforge.de/r/DebateReligion/comments/1s44rl/the_buddhist_position_on_gods_and_souls_xpost/

https://reddit.adminforge.de/r/DebateReligion/comments/19ehgy/to_buddhists_history_says_buddha_didnt_speak/

Samsara, anatman, nirvana, soteriology

https://reddit.adminforge.de/r/DebateReligion/comments/i0au3u/rebirth_is_incompatible_with_the_doctrine_of/

https://reddit.adminforge.de/r/DebateReligion/comments/5aaunf/question_for_buddhists_why_should_i_seek_personal/

https://reddit.adminforge.de/r/DebateReligion/comments/534aqi/from_a_zen_buddhist_rebirth_is_a_false/

https://reddit.adminforge.de/r/DebateReligion/comments/8bgx34/the_self_and_its_implications_for_rebirth/

https://reddit.adminforge.de/r/DebateReligion/comments/674zby/to_buddhists_what_is_your_eli5_explanation_for/

https://reddit.adminforge.de/r/DebateReligion/comments/3zr2yg/is_the_i_real/

https://reddit.adminforge.de/r/DebateReligion/comments/2yq2om/buddhists_what_differs_buddhism_from/

https://reddit.adminforge.de/r/DebateReligion/comments/gar9jm/reincarnation_is_undeniable/

https://reddit.adminforge.de/r/DebateReligion/comments/j34cwa/one_cannot_study_buddhism_without_also_studying/

https://reddit.adminforge.de/r/DebateReligion/comments/oerj9/to_buddhists_how_can_the_dalai_lama_say_if/

https://redditadminforge.de/r/DebateReligion/comments/1dlp5d/to_all_is_buddhism_without_rebirth_coherent/

https://reddit.adminforge.de/r/DebateReligion/comments/ol1jnn/anatanonself_contradicts_the_doctrine_of_karmic/

https://reddit.adminforge.de/r/DebateReligion/comments/iq41uj/a_brief_defense_of_not_necessarily_buddhist/

https://reddit.adminforge.de/r/DebateReligion/comments/qxafwz/the_hindubuddhist_afterlife_systems_are/

https://reddit.adminforge.de/r/DebateReligion/comments/8igj4b/the_buddhist_afterlife_system_is_the_most_fair/

https://reddit.adminforge.de/r/DebateReligion/comments/4n9970/can_a_buddhist_suffer_in_hell/

https://reddit.adminforge.de/r/DebateReligion/comments/2akdaq/to_buddhists_an_eternal_soul/

https://reddit.adminforge.de/r/DebateReligion/comments/y7dw4/to_buddhists_what_are_your_replies_to_these/

https://reddit.adminforge.de/r/DebateReligion/comments/139je1/to_buddhists_what_is_the_modern_view_on_buddhist/

https://reddit.adminforge.de/r/DebateReligion/comments/10bgf8/to_buddhists_if_there_is_no_reincarnation_isnt/

https://reddit.adminforge.de/r/DebateReligion/comments/18gg0n/to_buddhists_how_is_rebirth_really_significantly/

Karma, ethics

https://reddit.adminforge.de/r/DebateReligion/comments/11pvb6t/my_issue_with_karma/

https://reddit.adminforge.de/r/DebateReligion/comments/8xhnlx/mistaken_understanding_of_karma_when_viewed_from/

https://reddit.adminforge.de/r/DebateReligion/comments/2zf1bi/buddhistshindus_are_poverty_homosexuality_and/

https://reddit.adminforge.de/r/DebateReligion/comments/b8eoiv/karma_is_supported_by_scientific_evidence/

https://reddit.adminforge.de/r/DebateReligion/comments/1jp8ls/to_buddhists_is_killing_animals_as_a/

https://reddit.adminforge.de/r/DebateReligion/comments/lh4mw/many_buddhists_say_that_there_is_no_role_for/

Westernized Buddhism

https://reddit.adminforge.de/r/DebateReligion/comments/68bt6n/secular_buddhism_isnt_buddhism/

https://reddit.adminforge.de/r/DebateReligion/comments/g9vjkj/the_suicide_argument_ruins_the_prospects_for_a/

https://reddit.adminforge.de/r/DebateReligion/comments/57dodu/is_it_possible_to_be_a_devout_buddhist_and_also_a/

https://reddit.adminforge.de/r/DebateReligion/comments/1816ij/to_buddhists_do_you_recognize_sam_harris/

https://reddit.adminforge.de/r/DebateReligion/comments/1mgpev/are_there_substantial_differences_between_eastern/

https://reddit.adminforge.de/r/DebateReligion/comments/iw88w/to_buddhists_is_it_possible_for_someone_who/

https://reddit.adminforge.de/r/DebateReligion/comments/50lwdq/buddhists_and_secular_atheists_thoughts_on/

Upaya

https://reddit.adminforge.de/r/DebateReligion/comments/38z3mf/vajrayana_and_mahayana_buddhists_does_not_the/

Siddhi

https://reddit.adminforge.de/r/DebateReligion/comments/nt31pc/buddhism_is_doubtful_because_the_existence_of/

Maya, metaphysics, ontology

https://reddit.adminforge.de/r/DebateReligion/comments/pd97hh/despite_what_certain_critics_of_buddhism_allege/

https://reddit.adminforge.de/r/DebateReligion/comments/r6m1e/to_buddhists_if_everything_is_an_illusion_how_can/