I wouldn't say The Beatles are bad, and I'm definitely a fan, but I've heard their songs so many times in my life that I'm honestly sick of most of them. I would never actively choose to listen to their stuff/buy their records but if a song of theirs came on the radio, I wouldn't turn it off.
Also, I wasn't really into Dylan until we got the vinyl collection from my father in law, so now we own several of his albums, but he's got a lot of great songs... I can see that his voice might be a bit grating/annoying to some...