I remember reading them back in the early 90s (Robin Hood: Prince of Thieves, Far and Away, Back to the Future). They don’t seem to be a thing anymore (or am I just not noticing them).
As an aside I remember liking them but I was a preteen at the time so maybe they were terrible and I just liked the movies.
Film ones not so much, but Doctor Who does novelise their modern episodes especially since every Classic Who episode has been novelised. Most of them are fairly bare-bones retellings of the plot but the best expand and reimagine the story. The very best in that regard is absolutely Steven Moffat’s Day of the Doctor.
At the moment, the new episodes are getting their novelisations released digitally the Monday after they air with physical copies coming in January. It’s nearly the shortest turnaround time for an episode novelisation, only beaten by the novelisation for The Five Doctors coming out before the episode.