True, to some extent this is also an artefact of (comparatively) poor software optimisation for pi. In this case almost certainly zoom and others apps will be using cpu encoding/decoding rather than offloading.
Exacerbated by the Raspberry Pi 5 having lost all Hardware Video Encoding and H.264 Video Decoding. (That logic I don't follow at all)
The cartel charges pretty high fees for those.
Zoom in particular will be a browser-only experience as well, since there is not an arm Linux version of the app.