Piracy is inevitable, but in this case their model is much more robust that I would have predicted.
So basically they have this very secure scheme for getting movies to theaters, but everything else is full of holes. Makes you wonder if all the effort and cost to secure the theater distribution chain is worth it. If you're going to allow playback on devices in "adversarial" hands (streaming, home physical media playback), it's going to be incredibly difficult to restrict copying. Tightening up the one instance where the hardware and people operating it have less incentive to pirate (and more incentive to not pirate, given the risk to their theater business) seems like wasted effort.
Certainly this does make the case of a theater-only-first release nearly impossible to pirate. But there aren't quite as many of those anymore, and all this DRM must be expensive, both in the hardware/software, and in the logistics. I guess they've found it's worth it, but... oof.
Yes, that's the entire point. There are still tons of theater releases, that's literally the entire business of cinemas. The cost of DRM is peanuts next to their revenue, it's absolutely worth it to them. Nothing "oof" about it.