Edberg and Sampras played nothing alike. Edberg was a shark out there.
2001 Pete was a shell of what he once was and Fed still barely beat him, even when in a zone. Pete was not even that great of a pure serve and volleyer ( hes kind of sloppy) . He was a pure server. A win is a win though. Ask Rafter.
The only great pure serve and volleyer Roger faced was Rafter and he owned him. Rafter was a hack compared to Edberg. That style has been pushed out for a variety of reasons but it will come back when an athletic enough player can pull it off. Federer is not one of them (zero net game).
Multi surface variation against 90s era competition Fed would not dominate like he has done. Take this era we have now and put them on those surfaces and Fed would likely still be #1. He would own Wimbledon and the US Open. Against 90s competition no way.
Its actually pretty amazing that Pete was able to dominate the rankings like he did for so long in the 90s. He faced some truely great players all with different styles. Wimbledon kind of saved him I guess as far as the rankings go. The competition then was so deep and the point spread so broad that 1 major and some smaller titles was often enough to get you #1 status.