Kind of answered why many are choosing it for dev though. In many cases, it really is unknown and things are always changing. This is what many of these new technologies are good at, turning on a dime and accepting anything you throw at it. With that, you can refine the model from that tool into another tool like a properly designed RDBMS where you can better answer those questions.

I've pretty much switched to using only those tools for my dev projects due to the fact things are constantly changing like the devs you're working with. Then later on, go to a more refined model that will almost always beat the the prior approach.