I live in an old house and I was getting a mini-split for AC installed. I wanted to do ceiling cassettes, and the contractor told me it should be fine.

However, once they got up there and measured, it turns out that the 2x4s in my 115 year-old house are actually 2"x4", and so the cassette wouldn't fit unless they cut into the joists. We went with a different solution. But yeah just another example of enshittification, imo.