Much debate in this field so let's take a look at some of the myths and facts.
Anderson is a natural HW
1. As much as you haters like to believe, Anderson Silva is NOT a natural HW. He walks around at 220 (at most). That's his walk around weight and not his actual peak fighting weight. Much like how CroCop walks around at 235-240ish but fights at 220-225. Anderson started his career as a WW (even having a fight at LW) then moved onto MW in the latter of his career. He is getting older and if anything he is better suited for LHW at this point of his career. Fedor is a pudgy 220-230 but that's where he excels. He tends to struggle with smaller fighters more so than bigger ones. He would need to lose a lot of his fat to fight at LHW in which he would be in for a world of trouble considering the drastic skill disparity of HW and LHW fighters.
Bigger is better
2. Anderson Silva has fought much more well rounded, quicker fighters than Fedor. People claim the MW division is weak but it is filled with powerful, quick and well rounded fighters. The HW division, more specifically during Fedor's era were mostly crowded with 1 dimensional fighters (Hammerhouse, pro wrestlers, judokas, freakshows, etc) without the legit training, conditioning and gameplanning that is available today through a proper camp. Don't get me wrong. Fedor has some great wins under his belt but they were far from truly great fighters compared to the competition today. Fedor has an immense speed advantage over the slower lumbering fighters at HW (aside from the smaller ones like CC/Nog). Not that Silva's size advantage is even a reason for his dominant victories in the first place. Bigger isn't always better.
Level of competition
While Fedor staying undefeated for so long was a great achievement, that doesn't necessarily automatically equate greatness. The HW division is by far the weakest division even to this day where pro wrestlers can win the belt with just 3 fights under their belt but it was even weaker then. Anderson has fought his fair share of cans (and even lost to some) but never when he was the consensus #1 MW and at his peak like Fedor has. Fedor had been fighting some questionable fighters throughout his run as champion and #1 HW. Here are some that he fought AFTER becoming champion and had no business being in the ring with him. There were far more deserving fighters of a shot like Sergei, Barnett, CroCop and some others at the time.
Egidijus Valavicius
Kazuyuki Fujita (coming off getting demolished by CC and winning a staged pro wrestling "fight")
Gary Goodridge (biggest win over don frye....)
Yuji Nagata (0-1 coming off loss to CC)
Naoya Ogawa (7-0 over cans, great judoka but still had no business fighting Fedor)
Tsuyoshi Kosaka (understandable considering they just wanted him to avenge his loss)
Zulu (definition of a massacre waiting to happen, 4-0 over cans going into fight)
Mark Hunt (coming off a loss and fighting for the belt o_O)
Matt Lindland (bloated MW who Fedor had to cheat against by grabbing the ropes)
Hong Man Choi (1-0, not exactly a spectacular fighter in K-1 either)
Coleman 2 (Had no business in the ring with Fedor but was given the TITLE shot because they needed an American with a name for their US Pride show)
Here's a look at the questionable opposition on Anderson's end after becoming champion. Still far better fighters than Fedor's questionable competition.
Travis Lutter (3 fight win streak, coming off winning TUF for a title shot)
James Irvin (a test at 205 against a striker just to counter program a SF event)
Patrick Cote (5 fight win streak only replacing an injured Okami)
Thales Leites (14-1 going into fight with a win over Nate. Not sure why people questioned him as a challenger)
Now a look at their top 10 wins (taken from someone else)
Vitor Belfort (#6) - Didn't really deserve a shot imo and is nowhere near the striker of Anderson Silva as much as people clamored. We all saw what happened.
Chael Sonnen (#2) - The definitive #2 MW with wins over Okami, Marquardt and Filho.
Damian Maia (#5) - 12-1 going into fight replacing an injured Vitor. Had a submission win over Sonnen (who doesn't )
Forrest Griffin (#3 at LHW) - Coming off wins over Shogun and Rampage. Lost his belt just prior to Rashad in which he was winning until the middle of round 2.
Thales Leites (#7) - 14-1 with a win over Marquardt going into the fight.
Dan Henderson (#3) - The one fight everyone wanted to see and finally got when both were in their absolute prime.
Rich Franklin, twice (#1 and #2) 24-1 with his only loss coming to Machida going into Anderson bout. Picked up a win over Okami on his way back up to his second shot.
Nate Marquardt (#3) - 6 fight win streak with a win over Misaki going into Silva fight.
Jeremy Horn (#2) - completey dominated despite the huge experience advantage
Carlos Newton (#3 at WW) - His defining moment.
Alex Stiebling (#8 at LHW)
Lee Murray (#9)
Hayato Sakurai (#1 at WW) 18-0-2 when fighting Silva. God I love Mach.
Tetsuji Kato (#8 at WW)
Brett Rogers (#8) 10-0 with a win over a declining Arlovski. Not as skilled as people claimed but his record spoke for itself at that point in time.
Andrei Arlovski (#2) - Another fighter that got to take advantage of the weak HW division at the time. Had a 5 fight win streak against unranked opponents and 1 ranked in Werdum. How he was the #2 HW still baffles me.
Tim Sylvia (#3 at HW) - Had just gotten toyed with by 45 year old Randy and choked out by Zombie Nog prior to his fight with Fedor. Picked up a win over Brandon Vera (lol)
Mirko CroCop (#2) - Had a win over an injured Barnett, 3-0 Aleks, and a declining Igor. Massive hype leading up to bout after once being derailed by Randleman.
Mark Coleman (#8) - After being cut from the UFC after 3 consecutive losses, he goes on to beat Igor and Fujita to win the HWGP. Then he loses to Nog. Then beats Don Frye for a title shot against Fedor.
Antonio Rodrigo Nogueira, twice (#1 and #2) - My 2nd favorite fighter of all time. One of the toughest fighters with the toughest and most bad ass resume of all of them. Great wins for Fedor
Semy Schilt (#10) - Had a win over Funaki under his belt but a very limited susceptible ground game
Heath Herring (#3) - #1 contender at the time with wins over Erikson, Igor and Kerr.
There ya go. Not to mention AS has defended the title a record 8 times (13 consecutive wins total) against much more formidable competition while looking human only once against Sonnen. More top 10 wins and more wins over former/current champions.
People also seem to enjoy bringing up the Chonan/Takase sub from 8 years ago to question Anderson's abilities today for some reason. Anderson is older than Fedor and has just as many fights (more legit ones as well).
Why do people hate AS so much?
So what if he dances and is arrogant. That shouldn't have anything to do with being the GOAT. Muhammad Ali did the exact same thing to a much bigger extent and is lauded today as the GOAT in boxing. Silva has proven much more in his career, been #1 in 2 weight classes and is riding a 13 fight win streak against the top fighters in his weight class. Sorry you can't find pictures of him feeding geese or drinking vodka in a sauna. He is the most skilled fighter currently and is as dominant as can be.
Cheers to AS the #1 WW, MW, P4P greatest fighter of all time.