Will it work on X? xd
Sina
in the span of a single month is next to zero
It's much higher than zero, if let's say your ssd goes kaput & you try moving everything at once to a new one. That action by itself comes with risk, especially if the usb stick is very large & manufactured after covid. There is also the bit rot issue, usb sticks are useless as backup solutions for any use case, it's just a false sense of security.
I believe i can self-host a matrix client but no idea how well it will work with people currently having notifications by discord bot on their phone
In my opinion discord is not yet enshittified enough for these problems to be easily solved. Give it a couple more years, if matrix gains just a bit more traction, the scaffolding to do stuff like that will be worked out.
Probably not significantly less secure than Xorg itself, I wouldn't mind using in your place. DE security is usually not a huge problem, if someone can exploit these vulnerabilities usually you are quite bonked.
Remember most of what happens on screen is xorg, the wm is a simply interacting with xorg and other parts of your DE are simple user level programs like the panel etc..