Many of the problems you mentioned are already resolved though.

For example "global push-to-talk in Discord is always fun, especially with Wayland" was solved by using the [Global Shortcuts Portal](https://flatpak.github.io/xdg-desktop-portal/docs/doc-org.fr...).

Most desktop environments / window managers support that portal and stuff like Electron does too, so for example with Slack (installed over Flatpak) in can now toggle mute even If i dont focus Slack.