Given how much money goes into the budgets of mainstream titles these days, being risk averse is not a bad thing from an investor's POV. And ultimately, like it or not, profits are the point. Companies do not exist to foster social change, they exist to make money.
This is also why, as much as you hear some segments moan and complain about it, we have yearly installments of best selling franchises. They virtually guaranteed to make a profit.
However, I think the indie movement has the potential for a huge impact. They can make the games the big names won't, and act as a proof of concept. The things indie devs do that work well will get noticed by the big names and incorporated if/where applicable. If we're really going to see games that challenge the social status quo, I think we're going to see them there, first.
I don't exactly buy into the first part, since I feel Bioware hit something there when they were aiming to do something differently from other big name gaming companies, but I see your point.
But I definitely agree with your piece concerning indie developers- and it's one of the reasons why I'm a huge supporter for indie games. I just hope that those that do try and challenge the norms in mainstream video games do so in that they create something of quality and that they find the platform in which takes them to higher places.