Because eventually you'll get to the point where you've too much work to do and there's not enough people to delegate it to.

Hope you like being overworked!

It's a self-solving problem, though. At that point, every remaining senior+ engineer will be paid a bajillion dollars (like they are now) and companies will start to invest in actual training.

That worked so well for the finance system finding new Cobol programmers!

I am not convinced the finance system is struggling to find Cobol programmers. They certainly don't seem willing to pay them more on job listings.

When you read an article about a "skills shortage" it's usually more of a pay shortage and/or a terrible working conditions overage.

It is better to be overworked than underworked