That is an understatement: while sandbox restrictions can be bad for users, they can be a nightmare for developers who enter the feared 'app rejection cycles'.
Been using a Windows tablet recently, and there is a sharp line between the Win32 programs and the metro apps.
Thus you can say that a Windows tablet is a Windows desktop computer with Windows Mobile embedded.
As for the sandbox thing, i agree highly. Sadly the valley seems convinced that heavy sandboxing is the only way forward, no matter how much it infantilize the user.
Likely because the biggest proponents expect that they will always know the magic knock to get the sandbox to go away...
Yeah, didn't mean that the experience is flawless, just that it's overall better (IMHO) than what you get on the iPad Pro.
I think the hardcore sandboxing iOS forces doesn't really work well with "Pro" workflows. Say you want to edit a Word document and insert a picture - unless both your word processor app AND image-editing app are somehow integrated with dropbox / icloud, you can't do it; if you don't want to store your multi-gb image on "the cloud", you can't work with it; etc etc. Are these use-cases for laptops only? Yeah, maybe; but that's the sort of thing the iPad Pro was supposed to do.
I was (and still am) a big supporter of laptop-replacing tablets, but Apple didn't really manage to pull it off with this device. MS seems to have nailed it better, and I'll probably get a Surface-like as soon as prices come down a bit.