Currently, the most recent supported MC version is 1.20.1. Would it be possible to make it compatible with 1.20.4 as well?

Yes please, this!

plsssss🥹

I wanted to port it to 1.20.4, but after some reevaluation this probably would not happen. There's still uncertainty about forge/neoforge and other issues besides that.
I'll stick with major versions (in terms of playerbase) for now.

Keep in mind, that anyone is free to contribute. I will gladly accept a pull-request and will make a release if someone ports it.