They still wouldn't be able to disable the 24hr check system.
Or the restricted gifting/trading.
If people think pubs can just leave things as they've always been, well, that doesn't tally up with what MS has said. According to that, if a publisher 'opts out' that means used trade/gifting of their games is blocked entirely. Opting in means they're enabling trading, but only through the approved channels as controlled by the DRM system.