And I can assure you that there were a number of MS research developed tools for finding memory bugs that have been used for decades at MS. There was never a don’t look / don’t fix policy while I was there. Quite the contrary.

Was there ever a time, apart from the short monthlong stint in 2001 after Blaster, when Microsoft developers worked on fixing memory related bugs?

Automated tools (before the advent of A.I.) can only get you so far. The bugs being found by A.I. today could've been found by eyeballs if companies thought it worthwhile.