Securing the desktop protocol against keyloggers on Linux is like wearing a helmet when you’re walking down the street… yeah in theory it’s a good thing and would improve your safety, but it’s also wildly impractical and the things it protects you from are extremely unlikely.
And even if keyloggers were a huge everyday threat, you still have to allow for legit explicit uses of the technology (automation, accessibility etc.) But nah, they just said “we’re not implementing it at all”. What sense does that make?