Extended Covid eligibility, the transfer portal and the new no sit transfer rule has significantly changed recruiting. More competitive D1 programs are opting for older, more experienced transfer recruits. It’s pushed a lot of potential D1 players down the recruiting pipeline. For the next couple of years unless a player is positive he’s a D1 prospect he should probably be looking at lower levels.
Chances are the D1’s who have made contact like your son’s size. But at even the lowest level D1’s he has to cruise mid 80’s with great command and max 87/88 (given he’s a lefty).
It’s not hard to tell if a college program is genuinely interested or has a player on the “if we can’t get these other players” list. Phone calls are not recruiting. Enthusiastic phone calls after seeing him live makes him a suspect. Showing up additional times to watch means he’s on the radar. Receiving a verbal offer is a prospect.
A player should be looking for the best academic situation that potentially includes a positive baseball experience along with affordability, a social life and cultural fit.