No way in fucking hell is Company of Heroes "much more advanced" than Starcraft 2. It's a different breed of game. It's played completely differently, and frankly, it's not as good.
The reason "traditional" RTSes are preferred by professionals is because of the freedom of expression and the skill cap for which they allow. There is so much you can do if you just have the skills. Two pros may be equally fast, equally brilliant, but they play differently because they're different people.
Yes, Blizzard RTS games are polished. They're balanced, dynamic, strategic, and demanding. They're also traditional for more reasons than just nostalgia. They're traditional because that's better.