There is a major difference between a self publishing artist and a record label; the artist is primarily interested in gaining a wider audience and DRM is a hindrance here; the artist wants to increase his reach, he is less bothered by piracy.
The record label however is very worried about piracy - i argue that your position on the subject depends on your initial position in the hierarchy of things.
Not really. DRM reduces sales and end user reach. It reduces quality of what they offer. Unless you define as "good" those reasons they really use DRM for. And for sure none of them are good in general.
> they don't mind that it kills opportunities for growth in the future
Then it's even more pointless for anyone to think in this context that "what's good for business is good for America".
I'd rephrase it. To certain legacy business which can't compete and instead wants to use various combination of corrupted laws and lock-in to preserve their control over the market. There as well can be big business which is hurt by TPP and the like.
Except what is good for one business can be quite bad for another. And DRM in general is bad overall for business and economy (same as lock-in, growing monopoly and etc.). So this mantra doesn't sound meaningful.