There are a few more layers to this problem that no one seems to acknowledge.
What if someone DID come out of the woods and provided a Chromium fork that put Mv2 support back in. Then what? How do you install those extensions? Google won’t be allowing Mv2 extensions in their store anymore. Supposedly you’d need to download it directly from the developer and install it manually. That’s not great UX.
Maybe if the dev community came up with an alternative web store implementation that allowed Mv2 extensions, but that comes with a lot of other problems, to name a few: dev effort, costs for hosting the web app for the store and hosting the extensions themselves (which wouldn’t necessarily be expensive, but wouldn’t be free either), approval workflows for the extensions, etc. Thing is, though, all of that would require from devs a clear roadmap and a level of coordination that from my seat here, I don’t see a hint of it happening.
All of the above: either having a Chromium fork that allows installing Mv2 extensions manually, or implementing an alternative web store, is not a trivial effort, and then how many people will actually benefit from it? Those really concerned with effective adblocking, like us, are a tiny minority of the user base. Would the effort of maintaining a Chromium fork and/or a free(dom) webstore be worth it if very few people will actually use it?
I hate to say it, but yeah, Mv2 is doomed. I didn’t want to go back to Firefox, but I guess I’ll have to.
Many chromium browsera already have inbuilt adblockers that aren’t extensions, so they won’t be affected by MV3.
OTOH, MV3 versions of uBO and AdGuard are already more than enough for 99.9% of people.
So no, nothing will change, despite Mozilla’s undeserved fans’ hopes.