I don't understand this concern. How exactly are you copy/pasting code such that significant indentation causes "real problems"?

I remember the creators of Go explained [1] that they chose explicit block delimiters because of problems they saw when embedding snippets of Python in other languages. But this seems like a very niche kind of problem.

[1]: https://go.dev/talks/2012/splash.article#:~:text=we%20have%2...