Probably 99% of all drywall in the US is not painted directly, either. It is textured [0]. I'll go out on a limb and say that a substantial majority these days are orange peel texture on the walls and knockdown on the ceiling, made primarily with drywall mud (Artex seems to be essentially the same thing).

I'm not sure I would want a plaster skim in any case. I grew up in a house built in 1914 that had lath & plaster, and I've cursed the brittle plaster many times. We even had actual picture rails but my mom never liked to use them to actually hang pictures, amusingly enough.

[0] To be brutally honest, the texturing isn't for any particular reason aside from how well it hides minor imperfections. Having someone skim coat the walls and ceiling with a perfectly smooth finish is definitely a thing, but it's a good bit more labor intensive.

> Probably 99% of all drywall in the US is not painted directly, either.

I'm not sure about the exact numbers, but I'm pretty certain this is a vast overestimate.

I've painted a more than average number of interior walls in the US (both personally and professionally) and except for a few that were wood, adobe, or lath and plaster, all the rest involved painting directly on drywall. Sometimes the base paint was applied with a thick nap roller to achieve a degree of texture, but I never textured one with something else before painting.

All I can guess is that there are large regional or cultual differences here, and each of us is having a very localized experience.