‘Keep your identity small’ is a really good advice.
Even better is ‘remember your identity is fluid’.
We have a sea of identities within us. Multiple caps we wear, all at once.
Keep your identity fluid. It makes it easier to flow from your experience as an expert in what you know so much about, to promptly saying ‘oh, I don’t know this’ when discussing every other thing.
It makes it easier to connect with others who share either similar or opposing beliefs.
Make your identity fluid, without letting any of those expressions put you in a social cage.