I mean, look at the absolute frenzy it caused when Deion went to Colorado. And he'd been out of the league for 2 decades.
Granted, Belichick doesn't have the cool factor that Deion does with street cred and all that in the black community (just speaking frankly here, because it's a factor). But what he does have is 8 Super Bowl rings, 6 as a head coach.
If you're a parent who thinks your kid is NFL-caliber what better coach for him to play for?