Mentorship programs exist at most major companies, and new software engineers are not allowed to commit code willy-nilly - They pass code review, and less senior members of a team typically have more careful code review applied to their commits than more senior ones.

Mentorship programs that bypass the degree requirement are less common, but I made it through without a degree. I would love to see more of them, and more companies willing to help with work-study, but the challenges of that approach are real and may not have an easy solution.