You don't understand what pigeonholing really means.

When programmers talk about pigeonholing it usually means they like Python and want to go at Python conferences where people talk about math, science and machine learning, but they are pigeonholed in Java EE and surrounded by people who only talk about POJOs and beans.

And to top it all off, Java experience is badly regarded in Python tech companies and long term pigeonholing usually cuts you off from the world you want to be in.