They could and more likely did start with raw 5e implementation in prototype. And it's not something that normally goes into final product.
They have never shown any evidence of that. I find it unlikely since the first gameplay showcase looked like a DOS mod and to me was a disaster.
So they implemented 5e raw -> just to step back and make a D&D/DOS hybrid -> just to step back and make it more like D&D but missing many core features?
Doesn't make any sense to me.
