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.