I'm not in the industry, so I'd expect your cynicism to be greater, I suppose. I get that. But to be accurate (if at the expense of nitpicking):

"the end result is that we all wind up being treated as potential thieves"

We all are potential thieves from the perspective of anyone who doesn't know us; and if you have a valuable good, it's a far more reasonable (and profitable) assessment than "no one is a potential thief." It's the same stance you take when you design a website: "everyone is a potential hacker."

A potential thief, however, is not an actual thief, and to repeat what I said above, I don't believe DRM treats users as actual thieves: it treats them as potential thieves until they've authenticated and as honest users afterward. If you have to authenticate annoyingly often, it's a usability problem, but it doesn't change the essential dynamic.