From the article:
> The study discovered that the majority of users did not choose to block ads, with ad-blocking technology often activated by a third-party like their employer at a network level, their educational institution, security software they installed, or public Wi-Fi networks.
So, it's mostly not done by user opt-in. I'm further puzzled to find that you self-identified as a user with an adblocker not by your own choosing:
> My employer requires that we use adblockers.