[sheveksmath]

IMHO most languages are fairly similar to one another. Once you understand the underlying concepts and paradigm-level ideas, syntactical differences are pretty trivial to pick up.

What slows you down is when new ideas are introduced, like when you go from multi-paradigm languages like Python & Typescript to a more purely functional language like Haskell, or learning about ownership in Rust where there may be no equivalent in other languages. But ideally you only need to learn them once, and in a way that allows you to identify and apply them in a variety of contexts.

[bcrosby95]

Syntax may be trivial, but writing idiomatic code in that language isn't. Back in the late 90s for a class we had to write all our assignments in both Java and C++. The syntax translation was trivial. So in your sense, yes it was trivial.

But a professional C++ programmer would have designed their program a lot differently than the professional Java programmer. Simple syntax translation isn't good enough here.