Pitchingfan,
I totally get what you are saying. I really don't see a difference between a kid using college baseball as a way to advance himself professionally as an engineer or as a MLB player or coach. It is the same. As I see it, the trick is to know what you want to do with your skillset when that life decision presents itself.
I will disagree with you on your examples. You said your son knew that he could compete in the SEC because he played against the top travel teams. My son also competed against these top travel teams for two years. His team won the PG WWBA 16U tourney a few years ago. My son played travel baseball with future SEC and ACC players and there was no mistaking they had the physical tools to play at that level. We had studs up and down the lineup. While I will agree with you that it is absolutely necessary to play against top competition it is by no means a guarantee of future success because these are the most competitive and coveted roster positions in college baseball. Most of these guys will not start and will not play meaningful innings in college for many reasons. For this reason, I think the OPs question about transferring is an extremely valid question. In my experience, these SEC and ACC guys are the most active when it comes to transferring-out and my guess is your son played against a lot of these guys in travel baseball at one time or another.
As always, JMO. I wish your son well in his efforts to get to the MLB and eventually coaching.