What is the upper range of scores and GPAs? If the school has a published common data set, you can see the range of upper SAT scores and GPAs to be sure there is some overlap.
It really depends on the kid and on the school. Some kids that are very bright may not be all that interested in “deep” discussions and are content to be the top student and just hang out in their down time. They may not care if they aren’t learning as much as possible and will be happy for easy work. Others may really want to have fellow students that really want to work hard and tackle challenging material and get frustrated if the professor has to reduce the level of the class. That is not to say that lower SAT and GPAs mean that the students are not “deep” or are not capable of higher level discussion. Just that SOME schools with that profile may attract students that are there more to just get through and less to work as hard as they can.
If your student craves discussion-based classes, he should see if there is a way to gauge student interaction in those classes.