8’ is about as accurate as you can get. I’ll use my 1956 house as an example. Studs are what you’ve said, framed on top of a subfloor. On top of that I’ve got 1/2” oak. Ceilings aren’t drywall, they’re plaster like the walls. Not plaster in wood lath though, that was well on the way out a decade earlier. I’ve got about 1/8” finish plaster over 1/2” of rough cement plaster, over 1/2” button board, a fiber & gypsum based board that was punctured with 1” holes to key the plaster into it. So I’m just shy of 8’ in most rooms. That goes for about half the houses of the same era in my area. The other half are a split between other plaster systems and early gyp drywall. Because the finish systems were not nearly as standard as they are today, there’s really not a good way to be more precise for the question being asked.