More weight won't help if he doesn't know how to set up or follow a block.
Catching balls from a machine won't help if he has no idea when to catch them and when to get away from them.
He's too dumb.
These mistakes he makes are basic fundamental football that everyone who has ever caught a punt or kickoff knows. (Hell, people who have done nothing but watch football know when to let a punt go.)
The fact he has yet to figure them out, and gets actually worse in his decisions is enough to know he's too stupid to be productive.