Is it ok to not enjoy The Beatles ? Absolutely, rarely listen to them. I like their music but just don't choose to listen to them often.
They certainly weren't overrated though. Their output of classic songs and albums in about 6 years of recording music is phenomenal, not to mention how groundbreaking some of their music, songs like A Day In The Life, Tomorrow Never Knows etc. was and a lot of techniques used in recording today were pioneered on their records.
So it's hard to say they were overrated. They're so highly regarded in so many aspects of music for a good reason.
But music from a listening experience is subjective.