I like significant invitation, but I still wouldn’t choose it if I was designing a language today.

Functional-style programming has become much more popular since Python was designed in the 1990s, and there doesn’t seem to be a good way to have Python-like significant indentation and also support true anonymous functions.

True anonymous functions has nothing to do with indentation, ML derived languages are also indentation based.

Guido doesn't want them in the language, as simple as that.

Haskell has significant indentation and anonymous functions.

Haskell's significant indentation is, in my experience, much worse than Python's at fading into the background by matching what you would have done anyway.

As I understand it, Mojo’s goal is to be able to match state of the art performance for parallel algorithms and be able to use the exotic GPU hardware. A functional style is not necessarily productive in that context.

One interesting PL concept they implement are linear types https://mojolang.org/docs/std/traits/anytype/AnyType/

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