that code is pattern matching on an ast node; the complexity is from the data structure involved, not the language. there is no more concise way to match a specific node and get at the relevant fields, just various different forms of verbose code.

If anything, this matching on an AST is very readable and elegant, and that just convinced me that the syntax of Python seems really good to write a parser.

that AST parsing code looks like something written in Scala ...

seems like Scala is moving to more Python like and Python is moving to add some features from Scala.

I’m actually genuinely curious what alternative you might present from any language. I always thought that was relatively concise for such a complex data structure.

They're complaining about types, :=, and match.

That code has nothing to do with conciseness, he could've extracted the arguments in separate variables