performance: apps are running on a subset of XOrg and xWayland translates it to Wayland
RAM: if you have no XWayland apps anymore you save RAM
features: some apps may have more features on XOrg, some may have more on Wayland. OBS on XWayland can record keystrokes, QGis on XWayland has not broken dockable toolbars.
Yes, you get the usual Wayland benefits and tighter integration with the system. However certain applicants can be a little unstable when doing certain actions.
Depends on your distribution. Arch packages some electron apps in a way, where they can accept their own flags through a dedicated file. For others, it’s just a plain electron-flags.conf in your ~/.config
I would recommend visiting either the arch wiki, or tour distributions equivalent for details
Keep in mind that this does not apply to CEF apps, as that’s an entirely different framework
Probably not directly helpful, but Nix packages for Chromium and Electron apps are set up so that you can switch to native Wayland mode globally by setting an environment variable, NIXOS_OZONE_WL=1
I don't know of any global setting that isn't distro-specific.
For electron, if ELECTRON_OZONE_PLATFORM_HINT and electron-flags.conf don't work, you can also add --ozone-platform-hint=wayland to the end of Exec in each .desktop file (also works on Chromium, but not CEF AFAIK and sometimes CEF).
There's also --ozone-platform-hint=auto if you find yourself switching between X11 and Wayland.
Bad is relative. But I have some problems with scaling on a HiDPI display with some Electron apps. I think that might be solved if they were Wayland native.
If you need fractional scaling, they are unusable blurry. Some screens just need fractional scaling so for those setups it's almost essential to do this.
You need fractional scaling it your resolution is very high compared to the screen size. So something like a 15 inch 1440p screen would need 150% or 125% scaling because 100% is too small, 200% is too large but with anything in between, xwayland apps are blurry af.
Like X11, xwayland is not as secure as a pure Wayland environment but I think it's important to note that hundreds of thousands of desktop Linux users are likely still running X11.
So, in my opinion, it is not ideal to run xwayland but still completely acceptable for most users who don't have special security requirements.