They're teaching classes about web development and trying to react to the perceived market demands.

You're talking here about "if you're building X or Y, use ABC", but the class doesn't make that call, and they're trying to be attractive enough to students to choose them.

If I was a student, and was looking to "learn web development", and I search around for what I should learn to make myself attractive to employers... I'm very likely going to find unbounded recommendations for Angular, React and Node, almost without exception. Probably not even 'likely' - it really is what I see touted weekly in many groups that I'm a part of (user groups, online forums, etc).

The current situation for new folks trying to get in feels like a big echo chamber with bad recommendations reinforcing poor choices leading to more confused (and less productive) jr devs coming in to the field.