Definitely an oversight. I'll fix it right away. My apologies.

Thanks! Now you’ll just have the big traffic bump to deal with (:

I encountered the same issue. I refuse to whitelist blatant third-party trackers to use a service, so I checked it and then immediately closed the tab.

Not only that but it makes sharing the website a chore. Half the people you share it to will complain that it's not working at all... and try telling someone "here's a random link, make sure to disable your anti-trackers to visit it!"

Do general tracking blockers and mainstream lists block GTM though? I use a massive combined listed on a pi-hole so not sure which one it comes from. Just curious as there are, theoretically, non-invasive, non-ad tracking use cases for GTM.

I think Google ran out of good will/benefit of the doubt when it comes to tracking tech a long time ago. AFAIK, every blocker tool I use on any platform, which probably includes most of the well-known ones by now, will block GTM in the default configuration.

If a site doesn't work properly with GTM blocked, legitimate use case or not, personally I normally just move on. Unless I have a compelling reason to need that site, I won't make any attempt to work around it or change my blocker settings.

The only Google property I'm aware of that isn't routinely blocked by these kinds of tools now is Google Fonts, and I think some of them even block that by default now.

GTM is usually the wedge that marketing uses to pry its way into a site's code without engineering involvement, and thus blocking GTM will often prevent a huge list of other trackers, ads, and late-loading content changes from being loaded.

Late on this...but what are you using to block googletagmanager?

I'm running it in a private tab with all tracking protection and ublock off, and it is still slow. Slashdotted, maybe?