He never got the same creative freedom as he got while creating Citizen Kane. Citizen Kane wasn't a blockbuster of it's time as many theaters refused to play when they came under pressure from Hearst. Following which he spent his time in England.
His battle with Hearst has been documented in quite a few places[0].
"Not true there was a cabal preventing Orson from making more films. He simply never fulfilled himself after that magnificent start; his own fault - lack of self-discipline."[1]
See also this comment[2] right here in this HN story which goes into some more detail about Welles' chronic string of failed projects.
While Hearst may have done some damage, I think ultimately it was possible to Welles to recover, but he unfortunately spiraled down the drain instead.
[1] http://imdb.com/name/nm0936404/bio
[2] https://news.ycombinator.com/item?id=9503266He was a genius, but was unable to compromise to make commercial reality, and like many workaholics, his star burnt oh so brightly, but went out predictably fast.