Wilt was as great as you read. I saw him play in person late in his career, he still led the NBA in rebounding in his last season despite many good centers (Abdul-Jabbar, Bob Lanier, Nate Thurmond, Willis Reed, Wes Unseld, Walt Bellamy, Dave Cowens).
Wilt was better than a 6th man in XC, he finished third in the Phila. Public League Champs in XC in the early 1950's. Wali Jones also graduated from Overbrook HS and played with Wilt on the Phila. 76ers in the 1960's. Wali WON the Phila Public League XC Champs.
Wilt had great strength and speed as well as good hands. Also, defenses in his day were allowed a lot more contact than they are now. He would be pretty much the same player if he was in his prime today, dominating guys that lacked his strength and fundamentals.