I think the other problem is that, frankly, he's just not that good an actor. He's got one good movie, STAND BY ME, a couple of okay movies--LOST BOYS, GOONIES and GREMLINS--and the rest is pretty much crap.
I just wonder how much of it is simply that he hasn’t found fitting parts?
You have actors like Mel Gibson who can play anything you give him, but then you have actors who are great, if they play within their style. Jack Nicholson is that sort of actor. He, imo, can only play disfunctional parts: people with mean streaks or rascals, or nuts. Jack could not credibly play a family man.
I could see Feldman playing parts like hospital orderlies or government workers. Parts, where he’s part of the system, trapped and resigned to a lifetime of mediocrity.