Consider sheetrock to cover the problems.

Old houses may have asbestos and lead in the materials.

Latex painted over a glossy oil based paint.

Many older houses also had wallpaper on the ceilings. Before the paint roller became common (probably after WW II) it was easier for many people to DIY wallpaper than it was paint.

^^^Palimpsest, who knows such stuff?! If there’s ever a Houzz trivia tourney, I wanna be on your team!