I believe μBlock Origin is one of the add-ons that are actively monitored by Mozilla for security, which would make this automatically never apply to it. At least, it doesn't have the "This add-on is not actively monitored for security by Mozilla. Make sure you trust it before installing." warning that some add-ons have.

Comparing this to the web integrity API seems misinformed at best, and disingenuous at worse. It's not related either technologically or conceptually. I might agree that it could have some undesirable outcomes if they end up falling down the slippery slope, but this post does honestly sound like the hysteria you said you weren't trying to cause.

It sounds like a decent feature if used to protect things like banking sites from potentially invasive extensions. I disable my adblocker (only extension I use) for all those types of sites.

Please chill. Just because there was a really bad proposal doesn't mean everything coming out of browser companies is evil, especially Mozilla of all people. Specifially read this part on the page you linked:

If you are aware of the associated risk and still wish to allow add-ons disallowed on a site by Mozilla, you can do so from the Configuration Editor (about:config page)

So this just disables some extensions by default, but you can still enable them if you wish. That sounds very reasonable to me!

This is a pretty good hyperbolic rant. Nothing positive, all negative and an unsubstantiated "I can't prove it but I think they're doing this because..." which always gets the blood pumping and fingers flying. I give you an 8 out of 10. I could have given you a solid 10 on this effort if you had blamed the libs or a cabal for the nefarious deeds occurring in your about:config.

They didn't hide the release of the ~~bug~~ feature, they posted it on the Moz website for future patch notes.

The "for now" about the config setting actually made me chuckle. It's an option that you can optionally choose to disable. They're not testing their evil deeds on you by letting you turn it off.

Google is making their move because of their ad dollars at stake, Firefox will only benefit in terms of market share when that happens because they'll have another bump in user count in the form of a mini-exodus from Chrome, just like they did when Chrome announced stopping ad blockers from running in their browser. Almost all income from Moz comes from partnerships with the search providers listed in the browser search options. 0 dollars comes from advertising, so there is absolutely no reason for them to keep you from blocking advertisements on pages that only helps their competitor.

It's very clear to anyone that's paid attention that Moz is trying to protect a user that's downloaded a malicious addon(or one that's been hijacked) from siphoning data like login/pass on your banking site when, for example, the addon is supposed to only change the youtube site from displaying shorts in your feed. Prior to this ~~bug~~ feature, an addon that could see all data on a webpage could see all data on any webpage, whether it needed it on that page or not which is comically bad practice. They've finally implemented a method of restricting addons that don't need to see your most sensitive browsing from doing something nefarious like selling that data, using it against you or robbing you blind with it.

Here's the best part of it all though. Simply use a forked version of the browser if you feel you're using one now that an evil entity is trying to enslave you with by forcing you to see their competitor's advertisements(logic!). There's many "hardened" versions of Firefox, like librewolf, which strips Mozilla phone-home stuff like telemetry, sync, etc., The code is open source meaning you can build your own from the sourcecode, which will allow you to pore over every line, looking for hidden treasures that are trying to ruin your browsing experience. Or at least make an uninformed guess that is what it's doing.