i think a big factor that should into play when thinking about this is the mentality of Lewis, he was an arrogant son of a bitch and never entered a fight scared of anyone, something which a lot of Tyson opponents did
Lewis was a fighter that couldnt be intimidated by anyone or anything, and Tyson realised this when they did the press conference for the fight, and knew what was coming
Even back in his prime in the 80's, he relied so much on the fear factor and his opponents being scared, and while that wasnt why he won so many fights, he was also an excellent fighter back then, his lifestyle really killed his career(much like another favourite Bowe).
I think the general feeling is that Tyson was at his very best against Spinks, who was absolutely petrified in the ring, i think a better fight to judge a Lewis v Tyson fight back then would have been Tyson v Tucker, he was a big tall rangey guy who could box well, he just didnt have enough pop to deter Tyson and had drug issues by all accounts