The "not willing to train" thing is one of the biggest problems IMO. But also not a new one. It's rampant in my field of software dev.

Most people coming out of university aren't very qualified. Most have no understanding of how to actually program real world software, because they've only ever done university classes where their environments are usually nice and easy (possibly already setup), projects are super tiny, they can actually read all the code in the project (you cannot do that in real projects -- there's far too much code), and usually problems are kept minimal with no red herrings, unclear legacy code, etc.

Needless to say, most new grads just aren't that good at programming in a real project. Everyone in the field knows this. As a result, many companies don't hire new grads. Their advertised "entry level" position is actually more of a mid level position because they don't want to deal with this painful training period (which takes a lot of their senior devs time!). But it ends up making the field painful to enter. Reddit would constantly have threads from people lamenting that the field must be dying and every time it's some new grad or junior. IMO it's because they face this extra barrier. By comparison, senior devs will get daily emails from recruiters asking if they want a job.

It's very unsustainable.

Indeed: at least in knowledge based industries, everybody starts by working with a level of responsability were the natural mistakes a learning person does have limited impact.