It seems to me that a problem among pianists today is that many of them sound the same, and that sound is usually extremely clean, because they are all trying to find that same ideal tone. This is typically looked at as a good thing, but to the degree that pianists do it today, it just seems unnatural. One of the things people always try to avoid today is a harsh tone, but I think one's tone actually should be harsh sometimes, even in Mozart (he does have some very dark moments).
I just think that maybe striving for such an ideal tone sometimes results in an unnatural tone.
Anyone else?