“...suck just as bad...” Exactly.
Long have I read excellent SF by a host of talented writers. Those who claim that “there isn’t any good SF being writted anymore.” Hello?! Dan Simmons? Larry Niven? Charles Stross? Alastair Reynolds? Jack McDevitt? Neal Stephenson?
Jeez, people! READ!
Anyway, to your point, a few years ago one of my favorite sets of books, ‘Hyperion’ and ‘Fall of Hyperion’ by Dan Simmons were optioned by the author to a movie company. I was both horrified and elated. One, movies generally take excellent source materiel and make it suck, but two, Martin Scorsese (!) was the one optioning it and was set to direct.
It didn’t happen. As far as I know, it is still in limbo. Probably for the best...
But, the glory of ‘Ringworld’ on the big screen? Beautiful if done right, horrid if done by the usual Hollywood standards. ‘Foundation Trilogy’ would be a miniseries, but the utter cretins who run the Sci-Fi Channel would ruin it beyond comprehension.
Folks, read your SF. Let your brain to the work. Don’t leave it to a herd of Hollywood morons (I know, redundant) to screw it up.