I am running Mx-linux 21-3 with kde plasma 5.20.5 and when I remove the VLC component phonon4qt5-backend-vlc version 0.11.2-1 it also removed Dolphin file manager.
This should not occur as the component I removed is for VLC and cannot see any components that should be related to Dolphin?
And then an extraact from output of apt-cache rdepends phonon4qt5
phonon4qt5
Reverse Depends:
quassel-client
quassel
…bla-bla-bla…
dragonplayer dolphin
calligrastage
…bla-bla-bla…
Use apt-cache depends <package> and apt-cache rdepends <package> to climb the dependency tree.