That was Commander Vander bout, not Tyson. Alex had matched the consecutive ko streak of Mac Foster. But it was against similar caliber guys that Foster got the ko's against. But jumping up to fight Holyfield was a huge step up and he was a huge underdog going in. Like 12-1 if memory serves. A ranked guy w/ a glittering 24-0 w/ 24 ko's was a prohibitive underdog. Sure do not see that very often and especially considering the love of punchers----and that was taking on a former cruiser. But those ko's Stewart had were naturally against 3rd tier guys. And most of those bouts were on the MSG network so very few people even saw them. So more of a regional fighter w/ a glossy record stepping up to the big time. A quantum leap and a full magnitude beyond previous matches.
Come to think of it---Stewart had the same odds in the Tyson fight as he did going into the Holyfield bout. So clearly people had not seen him and were certainly not buying into him.
Galento held at least 3 ko wins over prime ranked contenders (N. Mann, Ettore, Nova) and ko wins over guys who were ranked at some point in their career like Natie Brown and Leroy Haynes.