Ooh, let me give you one data point on that.
I've had great success hiring juniors. One was a WebDev "bootcamp" graduate lady; I was hesitant but bit the bullet, and it paid of well. It was good for the team and, as she was coming from a highly-exploitative industry (Hospitality Industry) she was super grateful with all the perks and benefits in the Software Dev industry (shit, she was just grateful she wasn't sexually harassed... that's the state of things in hotel jobs apparently).
After that I hired another bootcamp graduate, Jr. guy with some mental handicap (sorry for my bad choice of words, English is not my first language). The dude had problems with oral communication; but given that we were a remote team, we had no problems communicating in writing through mail and slack. He was pretty good and passionate. And very grateful that we gave him the chance. I think he is still working in the company where I hired him :-)
Finally, at my current startup I hired another Jr dev, recently graduated from Software Eng. During my interview time I saw he was heavily "opinionated" but also open to accept that he didn't know stuff. I love opinionated+humble people. He has been amazing in my current team.
In my view, the problem with hiring Juniors is that a lot of times, companies are "lazy" in defining job openings. They want people that do everything and know everything. I compare it to the construction industry: As if someone hiring people to build a house wanted 30 architects/civil-engineer, and wouldnt want to hire lowly construction workers. The construction industry has matured enough to have very specific technical positions that can be filled by vast amount of workers.
This is what I've done. I try to break my teams so that I can (at least initially) provide a Jr developer with very specific, small, digestible tasks. It makes it way cheaper for me.
For example, I just recently hired a Jr. Frontend guy (just graduated) to work on Tooljet Dashboards. He was super happy to get the job, I could offer him around 40% more of what he was expecting, and I didn't have to ask a mid/sr level engineer to spend their time doing dashboards.