It's not a matter of hardware but community and online resources.
It is, and it takes time to get that. It also requires that (in the case of BeagleBone Black) the professional electronic engineers who start the project, let go as soon as they feasibly can and trust the enthusiasts take over. I think BBB is getting to that point. Once its stable enough they need to stop messing with it and let the community start churning out the equivalent of libraries and shields. Not to mention books and all the fantastic online project write-ups.
I also agree that there is nothing quite like this forum. A couple of years ago I used to contribute a lot. I occasionally try now, but invariably when I come to a question I could help someone with 3 people have already answered it well!