Why would Jones try and take him down? Because that is what he did in every fight, from what I know. He gets tired eventually on the feet, like he did with Gus. And not Gus' boxing was his main problem, but the fact that he couldn't take him down. and control him like he did with Cormier and the others.
We don't know how it would turn out since Jones never fought such a big recently and since recently he said he will probably never go to HW because he makes LHW too easy.
I know that people are impressed by his record, but he mostly fought smaller guys. MWs, injured LHWs and out of prime LHWs. Again, mostly! When he fought taller/bigger guys (Gus, OSP) it was very difficult for him. Not that Brock was this amazing UFC fighter. Not at all. Like you said, shitty boxing and couldn't take many punches in the face (although Reem and Cain were the best at this). I agree. But he was big AF with top wrestling.