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.
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.