Maybe the solution here is to just have some kind of legal penalty to losing user data due to incompetence. The problem here is that self taught programmers are going out to the real world and writing code that gets used to process sensitive info without any senior developer guiding them or reviewing.

If there was a penalty to the business, they would stop getting the bottom of the barrel programmer to work on their own. Yes it would make it a little harder to enter the market but any large business could still hire juniors and review their code properly.

In most other industries, you are responsible for your work. Usually you even need a formal certification first.