Nothing. There is nothing wrong with code generation in a production setting with "grown up" engineers who uses version control and knows the pitfalls.

The part in parenthesis is just a rant about education and how teachers use notepad and javac to teach Java.

So my point is the only thing students shouldn't use in an IDE is code generation.

But going from javac to Maven in CS1 would be insanely difficult; there are many prerequisites before one can use Maven. It may only work in top-tier schools.

I'd say quite the contrary:

If I had been given a zip with a basic pom file and the correct main and test directories I think I'd had a much simpler start.