I know McVay has this encylopedia mind for football, but watching him at press conferences doesn't inspire me to think he'd be any good in the booth. Knowledge alone doesn't necessarily qualify you to be good on TV. Often, quite the opposite.
Yeah, you can train him up some, but as someone who has brushed up against this industry a few times, I just don't think he has the personality to be an interesting commentator. (And honestly, I would find his voice a little irritating after a while)