Very good point.
Also the article made no mention of accreditation. AACSB is the gold standard for business schools. For prospective students, its important to be aware of that. The point being, if you cannot attend one of these top schools you can still get a quality business education from an AACSB accredited school.
The AACSB has diluted its brand so much that I would have a hard time seeing it still as a brand of excellence. It was at one time when it was hard to obtain accreditation from the AACSB. It is not so difficult now. Review the list of AACSB-accredited B-schools in the U.S. and you'll find a lot of very mediocre programs with accreditation.