I don’t disagree with you in principle, but this history is not quite right. IIRC the IE6 team was shut down. Basically only Mozilla and Apple were building browsers at scale until Chrome came along.
Yes, you are definitely missing a decade here. The internet explorer/edge team was shut down long after Google grabbed most of the market share.
Chrome was launched 2008; Safari had its first release in 2003. And I was using the early Phoenix builds (later the name change to Firefox happened) in 2001. The version of internet explorer around the time Chrome launched was v7. IE 6 was already old news by then. And IE 8 launched soon after the Chrome launch. 9, 10, and 11 followed. And then the switch to Edge happened; which was a complete rewrite of their browser engine. Only in 2020, MS announced switching to Chromium. So, that's about 12 years of MS trying to hold on before they finally gave up.
I might be misremembering?