“Does anybody else find his music boringly repetitive and overbearing and just not that good?”
It depends ... I find his music outstanding during a film. However, I find very few of his tracks worth listening to outside of that context (Superman theme, Raiders march, parts of the ESB soundtrack are some examples ... and even then I don’t know if it’s “great music” or nostalgia :-) ).
I generally prefer Howard Shore’s film scores, but I loved Williams’ score for War Horse, and I also loved Yoda’s theme from the Empire Strikes Back.
Williams’ scores often seem too obvious and bombastic.
Having said this, at least Williams (and Shore) are classically trained composers; too much of what I hear from film score composers now is so bad, the alleged music sounds like it was written by someone from the Obama Madrassa School of Music!!