As far as I know, that’s just always how it’s been for markdown, which is what Lemmy uses. So in order to be sure that your comment looks the way you want it to, it’s a good idea to use the Preview function, which Voyager thankfully also has under the 3 dots menu in the lower right.

@[email protected] also mentioned that you can put two spaces at the end of each word, and then it’ll count the one enter as a proper line break.
Like this. You can also do as I did, and just put a dash in front of everything, and then it’ll turn into an unordered list.