Also could an athlete get an academic scholarship and then walk on? Thinking of Emeka
Yes, but no.
So, Emeka certainly would have gotten academic aid from UConn as a student, but it almost certainly would not have been a free ride. He would have had to have paid something to attend. At the end of the day, why would he do that?
Andre Drummond was going to get a tuition bill - probably not a huge one, but definitely something.
Where a mix of academic and athletic comes in is usually in the non-revenue sports. Those sports have a low number of scholarships to offer, so they are broken into partial scholarships. If the student earns an academic scholarship, that just reduces their cost.
As for the NIL…boosters effectively paying tuition to skate scholarship limits is gonna bring some heat, so not a good idea.