It’s some apps still being broken, not the desktop. Screen sharing works perfectly fine for me in Slack, Teams (unofficial app by IsmaelMartinez) and web browsers.
There’s also X11 to Wayland video bridge that can be used as temporary workaround in unsupported apps.
Give Vesktop a try. It's a clone of discord and they say they support wayland for streaming just fine. It works fine but I haven't tried the wayland streaming thing yet.
I have it all installed. Discord native, discord flatkpak, vesktop. With vesktop you loose microphone sound auto detection and krysp. But yeah, sharing video works there also on the browser like firefox, but it's a tradeoff of the rest.
@devfuuu@jyte, try installing Discord with Snap (I had the same problem with a game - Veloren and Snap was the solution, aside the actual program, it downloads also all other dependencies, even if there are already installed on the PC and uses that one) 😁 (please report your success)