False analogy - RR is a de-facto standard in the web development community, hence my comparison to a building code.

No, RR is the de facto standard for the React community. And they're not doing training just on RR.

Claiming that because they made the most popular routing library for React it's shady to provide tutoring about it for profit is very much of a stretch in my book. Care to explain where exactly is the conflict of interest? Does that mean it's also shady to work as consultants? Where is the line drawn?

Do you really believe that noone is going to call them out if they started doing things deliberately to maximize profit (i.e. breaking changes without actual improvement, harder to understand than necessary APIs, etc)?

Ironically we typically spend less than 5% of a workshop talking about the router. So saying that we make breaking changes to sell tickets to our workshops is just naive. I can see how that's a gut reaction though, so no judgement on my end.