You can bet 300 new uBlock replacements to spring up practically overnight, some of them scams, reducing trust in the Google ecostystem.
Unfortunately it's a bigger problem.
Google doesn't plan to block uBlock Origin itself, but the APIs it uses to integrate into Chrome in order to function. This will effectively disable all adblockers on Chrome. uBlock won't be removed from the Chrome extension store, it will just have 90% of its functionality removed.
Additionally, this isn't a Chrome-only change, but a change in the open source Chromium, an upstream browser of Chrome all other Chrome-based browsers use (essentially everything aside from Firefox and Safari themselves).
The change itself is involved in changing the browser's "Manifest", a list of allowed API calls for extensions. The current one is called Manifest v2 and the new one was dubbed Manifest v3.
Theorethically Chromium-based browsers could "backport" Manifest v2 due to the open source nature of Chromium. However that is unlikely as it's projected to take a lot of resources to change, due mostly to security implications of the change.
Vendors of other Chromium-based browsers themselves have little to gain from making the change aside from name recognition for "allowing uBlock", which most users either wouldn't care for or already use Firefox, so the loss for Google isn't projected to be large, just as the gains for other vendors.
TLDR: uBlock won't be removed from the Chrome extension store, but the mechanisms through which it blocks ads will be blocked. The block isn't a change in Chrome but in Chromium and affects all Chromium-based brosers (all except Firefox and Safari). Other vendors could change that to allow adblockers but it's projected to take a lot of time and resources.
No, they will not, if they didn't already. Because convenience it key.
The browser war is over, and humans lost, corporations won. Google and other huge corporations control the biggest websites and most of the access to content on the internet.
They just need to make it inconvenient to use ad-blocking browsers.
They built their business on advertiser gambling, which seem to be flawed concept, because they keep on squeezing that tube for every penny more and more, in a race to the bottom.
But they are still in control of both browers and content so they have options to keep squeezing more.
So you want to use a ad blocker? Well, the browser that supports them might not be white listed (anymore) by the bot detector, and you have to solve captchas on every site you visit, until you come to your senses and use a browser, where ad blocking is no longer possible.
Oh, and all that is ok, because of "security". Because letting the users be in control of their devices and applications is "in-secure". They are just doing that to protect you from spam and scams, just trust them! Trust them, because they don't trust you!
I'm looking into the possibility of moving my organization to FF. Office of about 200 endpoints. The sticky wicket that I don't fully understand is Auth passthru to 365.
Its not the IT guys themselves, its the aggregate influence. One large school campus flips the switch to Firefox on their next image deployment its a drop in a bucket, but when 1000 schools, 2000 government agencies and 5000 businesses all suddenly stop using Chrome the graph starts to move, because laypeople just accept the default.
IT guys are like browser-influencers, they tell their parents what to use, friends, and so on. We all used to recommend Chrome, I don't anymore.