I guess either:

A) The most senior programmers simply don't visit Stack Overflow that much

B) The more senior you get, the less actual programming your work entails, and you again visit Stack Overflow.

Or something similar.

I assume you mean greater than 15 years, but my experience is that many of the programmers with 25+ years experience don't bother with things like Stack Exchange, especially if they're in a programming world that is "old and out of date" anyway.

10 years post college experience and I didn’t even realize there was a developer survey to answer.