I think in this context, "underrated" could be interpreted more as "easily dismissed as familiar or simple", compared to how we normally think of it as "overlooked", "lack of reputation", or "doesn't get any credit" etc.I'm not sure how Ringo can be underrated since he's the most famous drummer alive and there are endless examples of established drummers gushing about what an influence he was on them.
I feel that over the years all's probably been said about Ringo's strong drumming attributes - his time-keeping, innovative, original rhythms and approach, and his unique sound. However, one overwhelming phenomenon that I believe proves his class is other drummers' inability to match his distinctive feel (and, dare I say it - swing!) in any tribute act, or playing a Beatles' arrangement. I've heard good drummers master and play the beats and patterns but... it stil ain't Ringo!As a A fellow Seattle drummer, (Little Bill and the Bluenotes, El Funko) I admire Ringos ability to fit the song and general life attitudes. But, as a jazz guy at heart, I don't rate him in my top 10. ( I know, you have never heard of me either)