Anthony Tommasini, New York Times:
The overall level of technical proficiency in instrumental playing, especially on the piano, has increased steadily over time. Many piano teachers, critics and commentators have noted the phenomenon, which is not unlike what happens in sports. The four-minute mile seemed an impossibility until Roger Bannister made the breakthrough in 1954. Since then, runners have knocked nearly 17 seconds off Bannister’s time.
Something similar has long been occurring with pianists. And in the last decade or so the growth of technical proficiency has seemed exponential.[...]
[Early 20th century] audiences and critics tolerated a lot of playing that would be considered sloppy today. Listen to 1920s and ’30s recordings of the pianist Alfred Cortot, immensely respected in his day. He would probably not be admitted to Juilliard now. Despite the refinement and élan in his playing, his recording of Chopin’s 24 études from the early 1930s is, by today’s standards, littered with clinkers.
These days playing the Chopin études with comfort is practically an entry-level requirement for membership in the ranks of professional pianists.