I found this interesting. On both the Chrome blog and this EFF post, there is a quote from AdGuard CTO Andrey Meshkov. One of the quotes is favorable/neutral toward Google, while the other is more negative. It sounds like Meshkov may have changed his opinion.
Google blog ( https://developer.chrome.com/blog/resuming-the-transition-to... )
"As always, migrating to a new platform is a large undertaking, but we're very hopeful..."
EFF blog ( https://www.eff.org/deeplinks/2021/12/chrome-users-beware-ma... ) - sourced from AdGuard blog ( https://adguard.com/en/blog/manifestv3-timeline.html )
"Nearly all browser extensions as you know them today will be affected in some way..."