Serena Williams vs some of the other players in the mens top 100 would be a lot closer I'd think though.
Could you name a few of them?
Any man in the top 100 would beat her 6-0 6-0. Any man in the top 2000 would beat her easily. In fact any decent junior who's been playing this week would beat her as well. Speed and power aside, the men play with so many different spins and slices compared to the women (who are mostly ball bashers) that the gulf in class is huge.
In 1998 Serena and Venus challenged a guy called Karsten Braasch who was ranked 203 at the time. They played 1 set, he beat Serena 6-1 and Venus 6-2. He only served at 50% power and his warm up consisted of a round of golf and a couple of beers earlier that afternoon. He also used to smoke.
Chris Evert admitted that when she was no.1 she used to get beaten by her brother who only played at college level. Henin also tried to play a match vs a guy who was never even a pro and lost as well.