FWIW, the only other student from my D’s high school to attend the 5C’s in the past decade was a Mudder who is now at a T10 law school after working for a few years. (One is not a trend, of course, but proof of concept.) I don’t think the grade deflation is quite as much of a concern for law and business as for med school - med schools are notoriously insistent on near-perfection and indifferent to the context in which the GPA was achieved.
Re: the CMC econ department… I’m not aware that it’s written anywhere in stone that consortium students can never register for CMC econ classes, but it is well known that they are almost prohibitively difficult for non-CMC students to get into. Econ is the most popular in-house major for at CMC - more than 25% of CMC students major in econ - so the issue is some combination of demand exceeding supply, and wanting to keep their biggest draw exclusive (no insider knowledge here, just how it appears to me). I’ll touch base by PM but I’m not sure I have a lot more insight beyond that.
Socially speaking, I think some Mudders lead happily Mudd-centric lives while others participate more in pursuits that cross college lines and thus acquire a more mixed group of friends. But at least both options are there; if a Mudder enjoys having some friends who have never heard of Fourier, they are out there! The work is intense, for sure, but there are many who thrive on it and have fun as well. I just think that there’s a limit on how many significant non-academic commitments one can make, though of course there will always be those who seem like they can do it all.