programmers, and good ones imo, are almost always polyglots on some level, and i tend to think have a better than average ability to even pick up natural languages.
programming languages have a small, manageable and finite set of vocabulary, idioms, and constructs that most languages share but express differently depending on their intended use. a programmer fluent in programming will be able to pick up most languages. how those pieces are cobbled together to form more complicated abstractions becomes the skill obv.
that does not mean they'll be an expert right away, but it does mean they are usually competent enough at minimum to dive in and work with it just like any other tool -- they know they'll need a screwdriver, maybe a hammer, so they look up what it looks like and how it is used.
my daily drivers are python, cmake/Makefiles, c++, and c, with a sprinkling of bash, powershell.
i've worked with microsoft stacks C#/SQL, JavaScript, and i've written a ton of Lua. i've studied concepts and swe fundamentals in languages i don't really write code in and transcribe into code i do intend to write code in. i learned mostly using Lua first, then i picked up c++.
these are just the tools of my job overall. my main skill is communication and learning imo, and knowing which tools are better suited for a task at hand depending on requirements and limitations (mine or technical or both).