>>533770296
Well they aren't so annoying to work with anymore ever since Christopher died, but they are $$$expensive$$$. CA would have to pay many millions of dollars to use their IP but once they did, they'd have pretty much carte blanche to do whatever they want with it, given how much the Amazon show eviscerated the source material.
That being said, the Attila mod looks pretty promising so at least there's that in the meantime.