The best justification is probably that you lose an entire class of errors, but imo you improve language expressiveness.

Rust takes advantage of it's braces in good ways, I'd say.

It lets you paste some code and hit auto-format.

I'm actually kinda serious. Moving pieces of Python code around is unnecessarily error-prone. I don't consider this to be a good tradeoff.

Automatic, unambiguous indentation of code by editor.

Multi-line lambdas, for one.