I've read that Hunter didn't pursue the series because he wanted to act in movies, but that's not quite the same thing as him dropping the job because Desilu couldn't get him movie roles. Desilu didn't produce motion pictures; as far as I know, they were exclusively a television outfit.
Wrong on both counts.
make movies; one of them was a movie starring both Lucile Ball and Desi Arnaz Sr. called The Long, Long Trailer
: another was Forever, Darling
(produced as 'Zanra Productions') and the most well known was Yours, Mine and Ours
, (the original 1968 film) which made a ton of money at the box office.
As for Hunter not wanting to be on the show, Hunter did
want to be on the show; and expressed quite a lot of interest in his character, even going so far as to say that the show 'was based on the predictions that the Rand Corporation had projected for the future' (according to an article about Hunter in Starlog
many years ago.) If it seemed that Hunter didn't want to be on Star Trek, it was because his wife though that he was too big a star for TV (the same wife that would later divorce him and take him to the cleaners!)