I am a self-taught developer.

I think part of the reason is that "software development" job requirements have vastly expanded from 10-15 years ago. Speaking generally, a decent hirable engineer is now expected to not only be able to contribute full-stack (front and backend) but also do an amount of devops as well. The tools have become more specialized requiring greater experience to wield them. Nobody with less than 5 years exp is going to be at all productive and worth hiring IMO (note: that could include 4 years of freelancing while in college) Granted this is allowing very small teams to be highly productive. But you can't hire B-level or Jr. people at all.

So the experience level bar has been raised for the same position 10 years later.