All software ads exploits. Antivirus software mitigates already exploited systems.

And yes, some antivirus programs are infamous for being difficult to work with, but also remember that any vector that allows a user to easily override antivirus features can also be done by malicious software.

This is not true and bad security practice.

There are exploits that can be installed without a mistake made on the users part, the user can make a mistake, and almost every user downloads and open files regularly.

Windows is less secure than the other options, but the other options are not impenetrable. The biggest botnets are made of Linux IoT devices, and nobody opened the wrong email on they’re thermostat…

What a virus scanner will do is check your filesystem and possibly program memory for known footprints. A tool like this can save you from becoming a node on a botnet or being crypto locked. More importantly, if you work from home it can save your company from this issue as well!