You're right there are a bunch of software development jobs out there! Certainly enough that any skilled developer can find one.

That being said, for me as a manager, I like to hire people who demonstrate the ability to repeatedly ship products. It helps if they've owned that product from conception, through delivery all the way to support. That's a skill that is in great demand and I've never been disappointed when hiring someone with a great project portfolio on Github.

It doesn’t say anything about how well you can “ship” a product because you posted it to Github.

“shipping a product” involves knowing what trade offs to make, deadlines, working with QA, deployment strategies, documentation, not breaking preexisting code, etc., dealing with security and regulatory audits, etc.

Nothing about posting a pet project on Github gives a signal about shipping a product in the real world.

Sure it does. Are they solving a problem they were able to define? What does the shipping history for their project look like? Did they make interesting design choices and tradeoffs. Shipping any software is an accomplishment and does a lot more to demonstrate your skills than leetcode interviews.