ALF, welcome to the posting side. Various thoughts to consider...
Based on his current age, throwing velo and size, he is someone that many will project to be throwing 90+ in college. So, he will automatically get a lot of attention as a P. It sounds like he is an athletic and talented catcher as well. That will factor into a few things. Since he is a talented catcher, I don't think the lack of innings pitched will be a deterrent. In fact, many will tell you that is a good thing - far more bullets left. There are far more roster spots available as a P, so from a pure numbers standpoint, he has more demand and options as a P.
He went to Headfirst and you have mentioned targeting high academics, whether D1 or D3. D3 recruits quite late in the process, so you have plenty of time there. While D1 certainly recruits earlier, I would say that, generally, the high academic D1's are not on the fast track that some other D1's are. Additionally, if there is a kid that projects to throw 90+, many will find a spot, and some athletic $. That said, know that a large chunk of scholarship $ is still likely to come from academics.
Of course, for a player to go through the rigors of playing college baseball and balancing a heavy school load, he must love to play. I think most young players to have the dream as a position player more so than a pitcher. Some eventually come around to recognizing that their dream can be realized more as a P than a position player and find the same kind of love in that pursuit. Some do not. Every kid is different. If your son is currently still holding on to the dream as a position player, I would not deter him from that direction. If the thought of making it as a P becomes more appealing to him at some point, then you can address it at that time and likely still have plenty of options. I think that many of the truly great catchers were highly encouraged, at some point, to become pitchers because of their arm strength but they declined because being a position player was much more their passion.
As a side note... we have had catchers in our HS program who were converted to pitchers either in college or later in HS. One challenge I have seen with those guys is that they tend to throw more straight over the top (as catchers should do) so their fastballs are straight, not much movement. No matter how hard you throw, straight fastballs get hit hard by good hitters.
Another side note... the 10 mph drop is quite concerning.