I think that if "downloading apps users can't log into wastes their time" was the problem Apple was trying to solve, this would be a good (maybe better?) solution.
But the problem they're going after is bigger: how do you allow users to keep using their favorite apps (because most people aren't super privacy-conscious) while at the same time making sure those apps don't track users or sell their data? And, like it or not (and many people won't), I think forcing developers' hand is the only real way to make this happen.
