I disagree. You can get up and started in most language stacks fairly quickly. Keep focus, learn to sort advice into helpful and unhelpful buckets, and start building with a goal in mind.
For example - I hadn't touched fennel nor Love2d until about a month ago, and we made something happen.
You can do this too.
In contrast, I spent a ton of time trying to build other lisps that are designed to be embeddable on those consoles and got nowhere.
Fennel rocks. Such a pragmatic and well designed mini-language.
The article is about what it takes to really know a language. That's a bigger task. It takes months, if you work fast. That's how you write high-quality, maintainable software.
You can do this too.