Write more code. Stretch yourself. Learn how other people work and figure out how you can improve what they do, because that tends to be the bailiwick of what he's referring (mistakenly, IMO, but the bucket is probably fine even if the label isn't) as "real software development".

I didn't write Auster[0] for me, I wrote it because other people needed a tool and it fit the parameters. I'm not writing Modern[1] for me, I'm writing it because there's a hole in the ecosystem that somebody has to solve, and I'm a someone.

[0] - https://github.com/eropple/auster

[1] - https://github.com/modern-project/modern-ruby

If I knew, I would do it myself and wouldn't be afraid ;)

Probably the best advise is to learn as much as possible, but focus on basics. I feel people often mistake knowledge for skill and that harms them in the long run.

If you learn a concept, you can use it in anything you create. If you learn a framework, you will have to learn a new one in 5 years. Focus on transferable skills.