Ruiz wasn't much of a puncher, he didn't really cut off the ring, he wasn't as strong as Foreman and he didn't hit as hard. Roy Jones Jr running from Ruiz and winning a boring decision wouldn't mean Roy could do this against Foreman. Roy might run for a few rounds but he would be caught and brutally knocked out.
90s Formean was terrible at cutting off the ring. He managed to make Tommy Morrison elusive. Ruiz dropped Holyfield harder than anyone short of Bowe, and that includes Foreman.