Salaries in programmer are
really high compared to practically any other field that requires as little experience as programming does. If you want to verify this, put an ad in the paper for a junior position and say that you only require bootcamp experience, a related degree, or demonstrated experience with open source software. Offer the median salary for a software developer in your area. I bet you won't have enough time to interview even 1/10th of those people. And with the complete lack of credentials you are asking for, you will have practically nothing to help you narrow down the candidates. You might as well interview random selections.
We frequently say that there is a lack of talent out there. Anyone who has ever interviewed knows that this does not mean that there are a lack of applicants. It's just that you really, actually only want to hire one in 100 or one in 1000 of the people who apply. The vast majority of people applying for programming jobs want an easy job with a high salary, not a programming job.
If I'm hiring a junior, it really honestly doesn't matter if they are a new grad, just out of boot camp, a hobby programmer or have 2-3 years of experience. However, if they have 2-3 years of experience, you at least have some way of evaluating them. How do I evaluate new grads? Grades? How do I compare them against boot campers? I suppose with hobby programmers I can at least read their code!
Of course we ask for experience. Same thing goes at every level. People with a couple of years of experience are an absolute mixed bag. You'll get some who are awesome and you will get many who are horrible. At 5-10 years out at least they have opinions that they can talk about without resorting to "Well, I heard that X was crap and so I don't do that".
And this is broken record territory for me, but I'm old. I have something like 30 years of professional experience. Why are you talking about 5-10 years of experience like it's a ridiculous requirement? Why wouldn't you want at least 20 years of experience for a senior developer??? Even that is only half way through your career? Why are we hiring all these young, inexperienced, naive people into mission critical positions?
Are you sure people want "a new senior employee for the price of a junior one". To be very provocative: you've only even talked about experience levels that would be super junior in virtually every other professional career.
Hmm... Maybe I should conclude with "Get off my lawn" ;-) The above is really tongue in cheek, but I hope it provides a different perspective. I agree that we do not hire and train juniors properly, but I think that's mainly because we also do not hire seniors properly.