I am about 99% sure that most of today's fans - fans of Federer, Nadal, Djokovic etc. haven't seen much of 90s and perhaps at all. That's why they are very comfortable and idiots even to make sweeping generalization about the last decade players. Heck, if you transfer these very fans about 10 years back and tell them that, Nadal (essentially a clay court specialist first) would get the upper hand on Federer basically everywhere, they'd be very quick to laugh at you and tell you how big a moron you are. Some of them may well be all grown up, may well be as old as in their 30s, 40s, 50s etc. but this fanatic part of this, is as immature as it gets.
Come to think of it, it's great that players do get old and eventually retire, so there's hope for future tennis and forums that won't be monopolized by fans of one or two players. Amen to that.