some people for any number of reasons chose to not run an AV. be it a test machine or their daily driver.
true 99.999999999% will run one and probably should. it's the best/easiest way to protect your machine from the user's own mistakes. i'll never deny that fact.
but MS has decided that EVERYONE absolutely will run an AV whether they want to or not. so this and many other ways exist to disable this requirement for those who do not wish to partake. clearly enough people wish to not use one since so many ways exist to disable the requirement.
again i 100% agree that the average user should use one, but also 100% disagree that "average user" means every single person ever to sit in front of a computer. if you wish to take the risk on your personal system and not run an AV program, then MS should not stand in your way. it's what many many people hate about what windows has become. it is no longer an OS someone can adjust to be what they need. it is now a one size fits all method to provide MS with as much data to sell as possible
again you don't have to agree and may love everything about windows, but again enough people exist that don't like it, that there are many ways to disable/remove/tweak windows to try and take some sort of control back and make it what i need vs what MS tells me i will have.
you don't have to agree, or approve, but that does not mean you are the final answer and all must abide by your wishes.