It would be nice if there was a webcam on the market that took actual lenses so you could get free, legit depth of field. Paying $700 for a used DSLR that has a clean hdmi out is not appealing, especially when I have a mirrorless from the same company that could probably do the same with a firmware update (that will never come)
Once you have depth information integrated with a camera, then it should be pretty trivial to do background removal.
Whereas a 35mm f1.8 from Nikon is like $200 and whatever you mount it to is still going to need to do auto focusing and a bunch of other camera-y stuff to make it accessible to non photo geeks and then you’re going to need an off camera microphone so the entire call isn’t listening to your autofocus motor and...