I use my PC also for media, as it's connected to my TV by HDMI.
I have tried most KDE spins/distros, both on 5.2x and 6.x, and I noticed that on all other distros and Plasma versions, VLC uses between 8% - 12% cpu when I watch a 4K movie on my TV.
However on Solus it's only at about 3%. My PC is also noticeably cooler on touch while playing movies.
Note that it's only true for the KDE version, Budgie also sits at about 10% (Gnome + Cinnamon too on other distros) .
So I'm wondering what's the VLC "secret sauce" on Solus for KDE?
If there is no definitive answer I'd be curious to hear possible explanations for this from the devs.