Not sure if this specifically is the issue here but I’ll try to explain. Ignore it if I misunderstood your confusion.

Talents/streamers are people behind the avatars, it’s a different name for the same thing.

PLs (past lives) are the personas (name and avatar) used by streamers for their activities before their currently used one (people often stop or minimize activities of a specific persona when joining an agency/going indie etc).

This news is specifically about a an agency closing. Agency is a company which takes streamers under their wing as employees/contractors, (usually) providing them with a new persona and taking care of various legal, logistical and business matters. In return they take a chunk of money streamer earns (from donations, merch, collabs with companies etc).