I know it's asking for a lot, but it would be really cool if Pidgin would have 1st-class out-of-the-box support for Matrix.
I don't want to get into discussions if it's better than Jabber, because I don't really think it is, but since the momentum is on Matrix rather than XMPP, then I'd say that Pidgin could use the fact that currently Matrix lacks a proper client. By "proper client" I mean something that is feature-complete by standards of year 2000 (actually good software, like Pidgin), not 2020 (which features broken, half-ass web prototypes that people call software).
It would probably help with fighting the parasites like Discord, which is way too popular than it should be.