The thing is that those companies want to protect themselves against piracy. The issue with Apple is essentially the same, they’re kind of burned by people (in China) using Enterprise certificated to setup alt app stores that sell or offer pirated applications. Yes, that’s a big thing in China. There are also a couple of examples outside China but I believe you get the point.
This is… half unjustifiable corporate grief, half legit piracy concerns that would eat into their profits. I would like to see a law that forced them to have everything unlocked on the first day but I also see how it won’t be feasible…