Max has an ultimate tier which advertises "ad free". There are still ads which they call promotional and they claim that since there is a skip button it is ad free. If I were a lawyer, I would sue them for false advertising.
Nobody enjoys seeing an ad for whatever abomination the demon anderson cooper is in.

Amazon Prime Video does the same thing, displaying trailers for their upcoming movies/series.

The saving graces that still make paying for "ad free" on streaming providers worthwhile are:

A) It's only in-house trailers and promos, so still no outside commercials

B) It's only at the beginning, so it doesn't interrupt you mid-movie/show

and most importantly

C) There's a skip button (as you mentioned)


Plus, if you'll recall from back in the day of the premium movie channels on cable or satellite (HBO/Showtime/et al), they were the same way. No commercial interruptions during the content, but in between movies they'd show a few ads/trailers for their upcoming shows and movies.