https://community.kde.org/KDE_Gear/21.12_Release_notes
kde-apps/krfb will have a hard dependency on media-video/pipewire. We'll need to add prerequisite instructions to the Gentoo KDE Wiki for how to either configure pipewire or pulseaudio and link to the respective guides. USE=pulseaudio was never made the default in Plasma profile so we could focus right away on pipewire. USE=screencast in various Plasma packages has so far not been default enabled either but should be considered starting from upcoming media-video/pipewire-0.3.40 stabilisation.