It's a forcing of their narrow opinion on what should be allowed onto the ecosystem at large, because all of these things are connected. You can leave to a different DE/distro, but if every DE is doing its own thing for global hotkeys or whatever, then software in the ecosystem is going to be hacky/bespoke or have an unreasonable maintenance burden.
Even if you in particular can move elsewhere the ecosystem is still held back. We only recently got consensus on apps being able to request a window position on screen, which is something x11, macos, and windows all allow you to do. CSD and tray icons are other examples of things found everywhere else that they did not want to support. Some applications are just broken without tray icon support.
This bleeds over into work for folks releasing software for Linux in general. By not supporting SSD they were pushing the burden of drawing window decorations onto every single app author, and while most frameworks will handle this, it's not like everyone is using qt or gtk. App authors will get bug reports and the burden of releasing software on Linux needlessly climbs again.
Hard to convey how unreasonable I feel their stance was on tray icons / SSD. It should be the domain of the DE from a conceptual but also practical point of view, even from just the amount of work involved. It reminds me of LSP's enabling text editors to have great support for every language. And again, Gnome was the odd man out in this, they want extra attention and work when Linux is the lowest desktop marketshare by far, and they themselves are not the overwhelming majority but they are large enough that you really do need to make sure your software runs well on Gnome even if you want to support Linux.
People think Gnome push stuff down your throat because they have the power and influence to impact the ecosystem, and they use that power and influence to die on absolutely absurd hills.