Linux

It looks like this is more like three different messages that are worded a little weirdly, making it have a more confusing single meaning.

The barf emoji (where they used H1, by the way. Why, I have no idea) implies that they dislike either PaperWM or GNOME, likely the latter given that GNOME and KDE Plasma have a kind of holy war thing going on between its users, and this person (who uses Plasma) is the kind of person who has extreme opinions it looks like.

I wish them all the best , except if they're part of fascist open source, in which case, they can get bent.

This part is worded poorly, especially given the preceding barf emoji making you think it's a negative opinion for the whole comment. They are positive about Niri, but IF they turn out to be not very nice then they can "get bent" (whatever that means)

But then again, I have my KDE task manager so that it only shows tasks from the current screen on it, and even I sometimes find that disorientating.

And this bit is just talking about how they won't really take advantage of tiling WMs anyways given that windowed DEs are already "disorienting"