alt Hacker NewsI've never worked in a corporate environment beyond client projects.
Picked up a book on XHTML (no, that isn't a typo) and CSS in 2007, just kept trying to build stuff I wanted to build and backfilling knowledge as I went. Not only is it possible, it's preferred. ~20 years in and I've learned how to build my own full-stack JS framework, deployment infra, a CSS framework, and an embedded database to boot.
Not one drop of this would have been possible had I taken the traditional corporate track.
All of this is possible on a corporate track. Ability to build frameworks and tools do qualify a person as at least a solid mid-level professional, not having corporate experience and associated skills can be a pretty big gap in their CV.