My thoughts:
1. "Overrated" isn't a word with meaning when applied to classical music - who is doing the rating?
2. I relistened to my old recordings of "highly rated" from the 1950's & 60's-the ones I grew up with, and immediately "downrated" them because, at my present ripe old age, I could not follow the phrasings taken in the 1st movement, which made no sense from a lyrical perspective and felt totally plodding. Apparently, those pianists read the tempo marking (adagio sostenuto) without noting Beethoven's 2/2 time signature. There must be only 2 beats per measure; those beats represent a slow tempo, but still allow for complete lyrical phrases. Many current day pianists implement that change.
3. The middle movement, likewise, dragged on with no personality in my old recordings, with 3 beats per measure and sometimes 6. But it's a minuet! Try thinking of anyone dancing to it. In dance, one experiences 1 downbeat per measure, and would want the tempo to accommodate that fact. If you play it like a danceable minuet, you can fully appreciate the syncopation in the B section, as well as what I think was Beethoven's intent as merely to transition to the last movement (perhaps as in the Appassionata, sonata and several others).
4. The 3rd movement really must be played Presto, if you can do it cleanly. But again, the time signature assists proper interpretation. Playing in 4 at that speed, the incredible energy and momentum generated by the 1st theme and its development is what this piece is about; the lyrical 2nd theme must really sing, but without losing that momentum.
5. Overrated? Or under-nuanced performances drilled into our brains from hearing them too many times?