Sort of my sentiments. I'd not be quite as critical, if only because there were a lot of pianists from those years with less than full agility. Gil Coggins and Wade Legge come to mind right away- good, interesting even, players, but nobody would ever accuse them of blinding virtuosity, to put it mildly.
The wildcard for RP, though, is McCoy Tyner's citing of him as a key influence in terms of voicings. First time I read this, I thought, "WTF?", but going back and relistening, I can hear moments where Powell used some pretty interesting, non-beboppish voicings in his comps and solos.
Just goes to show ya', although what, I can't say.