Dhsu, I once made a topic that deals with what you're saying. Here's what I said:
First, watch this (and the other 2 parts, if you have time):
http://youtube.com/watch?v=Qb6ORAW3-MQ
If you're one of those people who thinks that Sonic isn't about speed, this should fix your broken perspective. If Sonic 2 was fast, surely the entire franchise should exhibit the same speed in all of it's main entries. I mean, look at Joe move. It's simply beautiful to see how he tears thru these levels with such grace and finesse. This is how I'd picture Sonic really moving if he had control of himself during his games.
Gosh, I mean, just look at what he does to Aquatic Ruins Zone. He rips it UP in there, and he's underwater a fair amount of the time!
Granted, the video linked above is a speed run, and most people don't achieve such ridiculous speeds (myself included). Yet still, you're not going to see the same mind-blowing acrobatics in a Super Mario Bros. speed run or a Metroid Fusion speed run. Those speed runs showcase a different kind of style and talent. But not pure speed like this.