I'm willingly pigeonholing myself as a "software developer mostly working on the JVM" just to be honest about my (current) main strengths/experince. Throwing me into a Go/Python/whatever project would first need some time for me to get up to speed with the language.

I do the same, but I also happen to acknowledge that I slowly transition into X Developer, depending on which project I am on.

It is the usual "Jack of all trades, master of none." consulting, but it does come in handy when we need to deal with mixed stacks end-to-end.