I voted a tentative No.
Troy was clearly very high class and an above average Derby winner. I believe Hern and Carson rated him as their best Epsom horse, purely on his performance on the day. They considered Nashwan at his very best over shorter distances.
I don’t believe Troy did enough to be considered amongst the all time greats, although I wouldn’t argue too strongly with those people who believe he was. It is a game of opinions.