Expertise should increase precision, not arrogance.

Real expertise narrows claims. You know where the boundaries are, which cases are exceptions, and how often the standard answer is wrong, so you speak more carefully rather than more grandly. Arrogance tends to appear at the stage where someone knows a lot and has not yet met the limits.

If you have expertise, check whether it is showing up as precision or as authority. Are you explaining the conditions or issuing verdicts. And when you are the non-expert, weight the person who tells you where their knowledge runs out more heavily than the one who never does.