First, colleges, at not the top ranked research schools aren’t about teaching. They’re about research. You’re expected to learn in your own, else why else have competitive admissions?

Second, my wife’s teaching degree, though supposedly highly ranked, was a joke, coming after her degree in natural resources. She was cruised by with a 4.0, and even so, was constantly dinged for things like not using enough colors in sticky-note bookmarks or highlights, not highlighting enough, etc. It was an absolute joke. She absolutely didn’t learn to teach either.

Can anyone teach? No, but a college degree isn’t the metric either. It is however a barrier to entry that keeps poorer people from joining the profession and also reinforces that institutional accolades are the mark of success, when really they are no such thing - they are an indicator of future success. Requiring four year degrees results in watering down degrees and erasing such indicators.