As a drummer (thanks to Ringo's inspiration) I can unequivocally declare: yes...he is indeed an amazing drummer, for many reasons.
His childhood full of debilitating illness...playing drums, while therapy, is still a rather strenuous activity.
He was the best drummer in Liverpool at the time according to many sources, including the Beatles.
He brought personality & a common man quality to the group at the start which helped propel them to fame.
He was able to play Latin (I Feel Fine) pop, rock, and various time signatures one after another (All You Need Is Love, Happiness Is A Warm Gun, etc.) which is difficult to do and do well.
He virtually invented (or perhaps more to the point brought to the fore) the open hi-hat technique that gave a solid wash of cymbals to the backing of a song. Rocking!
He had a strong back beat (bass drum) that brought that aspect to the fore as well.
He inspired countless, countless people to take up drums, many of whom went on to fame themselves.
Songs of note: Rain (his favorite), A Day In The Life (the fills he did were absolutely perfect, and no one would have ever played them as musically as that), The End (Abbey Road), She Said She Said, and many more. His inventive yet supportive style and laid back personality was perfect for the Beatles. No other drummer could have added so much.
Technical ability is nothing without feeling, without empathy and understanding. And maybe some love. And he brought all that and more to the group.
He was *never* a lesser member than anyone else. It was a four poster bed and he held up his end as much as anyone else.