I cannot disagree with you that many of today’s classical pianists "are too tightly bound by a rigid performance controlled by the original score". However, most of Claudio Arrau’s recordings will demonstrate quite the opposite: he is very interpretative, which is why some individuals, who are classically trained, may not like him as much, as he plays what is written on the score, as well as what is not written, "between the notes," shall we say. However, not all of Arrau’s recordings are magnificent, as he has some mediocre recordings of Beethoven’s Piano Concertos, and Gilels might have the best recording of those concertos that I’ve heard.
As mentioned above, all listed here are excellent, but many are simply master technicians at playing the right keys right on time (Ashkenazy, Lang, Horowitz, et al), without the feeling or emotion behind the music.

