What it changed for me personally is that I'm no longer exposed to such extensions because I don't grant any extension permissions which would allow malicious activity. I'm sure Raymond Hill is right that some functionality couldn't make it to his MV3 adblocker, but whatever it is I'm not missing it.
>some functionality couldn't make it to his MV3 adblocker
One of the things that didn't make it is the entire request control dashboard. No more granular reporting or controls, at all. No more "medium mode" or "hard mode" (blocking unknown domains by default and making exceptions as you go). Sure, if you didn't use it before, you won't miss it.
Yeah I get it, but I think we're talking past each other. You're a knowledgeable user and the new APIs made it possible not to worry about uBlock getting hijacked. I'm an extension developer, and I see an appalling disconnect between what Google says and the reality of Chrome extensions and Chrome Web Store for regular (non-technical) users.