Reasons I don't use IE would include:
All Msoft business software is target-rich environment for computer viruses particularly since it is all programmable and meant for systems integration. That's wonderful for a company which requires systems integration projects and which has five people whose job it is to keep the lid down on cybernetic mayhem; for an individual to have a computer with programmable applications facing the internet is like walking around in the Bronx with a kick-me sign on.
Bill Gates is the polar opposite of Col. Sanders who just does the one thing and gets good at it; Gates tries to do everything and never does any one thing the best possible.
IE code was originally hacked from Mosaic code and likely still is based on Mosaic while you'd assume that Chrome and Firefox amounted to newer and better code.