You could download the Chromium source and patch it to change the extensions APIs (or better, just use Firefox), but the majority of users won't do this, and extension writers aren't going to make a version for a patched Chromium browser unless it has significant market share and support.
[1] https://nordvpn.com/blog/manifest-v3-ad-blockers/
[2] https://www.eff.org/deeplinks/2021/12/chrome-users-beware-ma...
Better to just use a browser that actually respects its users.
Unless you’re running that 20%, Google controls it, and they basically write the standards anymore.
I thought this is rather obvious, at least for those worried about experience. Do you think all those who realize they're suffering from ads don't think about using non-Chromium browser?