How is it not programming ?

Unless you write assembly or lower, you have no standing here. Mocking children for learning a high-level language is all sorts of wrong in so many ways.

It's Turing complete, isn't it?

Because it's a programming language, where they learn to program, and then make programs.

How do you define a programming language? What qualities must it have to be one that Scratch lacks?

How old are you?

Scratch is a programming language? I don't see the problem here and kids have to start somewhere on their programming journey.

Go bonkers. Go crazy. Shake your fist at clouds. Get jokerfied.