Everett

The upcoming Cosmic desktop by Pop!_OS has the exact feature you’re describing.

KOReader is a pretty decent ereader option, it matches what I put on my Kobo.

I doubt many people will be willing to de-bloat their WIndows install, because there is a lot of overlap between the type of person that would be willing to go through all the hurdles of de-bloating, and the type of person that is already on Linux.

I start with Subscribed/Active to get my fix for the content I want to see, and then Subscribed/New to contribute comments that aren’t parroting what others have already said.