PABaseball, I disagree. Classes at a HA are taught at a higher level.
When he was still in high school, my older son took Physics 101 at our local state university. He went to an Ivy, and took Physics 102 there. Then he retook Physics 101 there also. We asked him why, he said there was no comparison in the way it was taught, and he would not be prepared for the upper-level classes (his major) unless he took the Ivy intro class.
Professors give readings and assignments that are more complex and demanding when they can expect more from the students. The work done in groups, and the class discussions, are different. Never mind the difference in funding and research and summer opportunities at super-wealthy private universities.
Do you need all that extra rigor? Depends what you want to do after. Of course a bright student will do fine anywhere, especially if he exerts himself to seek out opportunities. Just like a great baseball player can get drafted from anywhere. Why would a great baseball player rather play in the SEC? Maybe because of the better teaching, more rigorous expectations, better teammates, better facilities, better competition? How is baseball different from academics in this respect?
Despite all that, my answer to the OP would be, if he is being looked at by pro scouts already and has a high scholarship offer to a P5 school, why not go for it? Keeping in mind all the warnings on this site, about what has happened to D1 baseball with transfers, and unless he wants to major in something the baseball coach won't let him. He will choose what to make of his academics, wherever he is. But if he is cut from the baseball team, he might not want to stay.