If he was giving professional software advice I think him giving mediocre software advice would be a bad thing. However this is a video designed for people with little to no experience, and the terminology/technology should reflect that.

There is a saying, don’t let perfect be the enemy of good, and I think that applies here. just getting a project started and done is a good thing, even if your software practices are bad, those come with more practice anyway. When you are learning a new skill you start with small pieces and then add onto it over time.I wouldn’t start teaching someone micro optimizations or design patterns before I teach them how a for loop works.

Now you can make an argument to just learn best practices from the start, and generally I agree with that, however some people get overwhelmed with all the concepts at once and so I see no real issue in learning one way first then learning a better way second.