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.
They were still a thing in the 2010’s, at least, I remember the Pacific Rim novelization. And I know they do novelizations of a lot of Disney stuff, even the Disney Channel movies, if they have good brand tie-ins/merch…