Personally, I fell asleep watching the first movie, which I don't think is the effect erotica is supposed to have.
More telling, students of mine who whipped out their fake IDs and got in to see it generally reported that they were bored. Not the reaction that I was expecting!
Clearly, some people liked it. But I think the movies mostly rode on the success of the books. A lot of people went to see the movies because of that.
As far as the future of Hollywood is concerned, I think movie theaters are in decline in the same way bookstores are. When you can watch the movie at home, and the popcorn is a lot cheaper, why not do it that way? Theaters are still open partially for reasons of nostalgia. I notice the Stranger Things two-hour finale is being show in theaters as well as on Netflix. And some movies that become cult favorites continue to pack late night showings.
As far as movie length is concerned, the streaming services are still packed with two-hour movies and one-hour TV shows. Attracting viewers doesn't seem to be a problem yet. Shorter forms exist, but they aren't yet dominant, at least as far as I can tell, though they are certainly popular on venues like YouTube.