At the risk of appearing less refined, I still fit a bit into your original category. Solo piano continues to be me least favorite, but not necessarily disliked, instrument. I can appreciate amazing piano talent from poor, in multiple genres, but if given the choice between a solo piano CD and any other solo instrument, I'll almost always go with the other.

Piano mixed into a orchestra, jazz group, rock band etc. is a whole other matter. I generally enjoy what it adds as a piece of the bigger puzzle so I'm not sure why it's my least favorite solo item. No need to analyze it I guess, one likes what they like.
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