Well i didnt say nobody does, but its not one of the thing i usually see among group's houserules i play with so i dont know how popular this change is.
I wished it was in a Wandering Monster's poll so we see some results.
Since you have Mike Mearl's ear, why don't you ask him to do precisely that. If they "go by survey data", as they claim to, that should be a given.
Not sure if others in this thread can see the temp results or not, but all three options are virtually neck and neck so far. If you have to err, err on the side of caution, err on the side of tradition.
Changes for their own sake are a bad thing. Suddenly the DS crowd wants super-fast-legged halflings and gnomes, when they never, EVER complained about that in ANY forum venue before. I'd never even heard of a single person complain about that in real life, either. If you pick such a race, you are accepting their slower speed. Sometimes a handicap is a good opportunity for roleplaying and makes you more fully immersed in your character.
Uniform speeds wrecks immersion, it's simply ridiculous and gamist on its face. Sure, mythological dwarves and halflings could have disproportionately fast legs, just like Tolkien goblins, but they didn't in LOTR, and they haven't in most of D&D's 40+ year history.
Plague, get Mike's attention on this, and you'd be doing the entire community a service. Also, ask him what he thinks about apprentice fighters having 100% chance of successful attacks on every attack of their entire career. He definitely has been reading this stuff.
The finish line is near, I hope classic D&D mindset wins (which is that races are different, and fighters don't succeed on every single attack), so that I can put my money and time into this game.