> I wish Chrome and Firefox would adopt a content blocking system similar to Safari...
This is exactly what Chrome's Manifest v3 offers. As they put it: "There's a new declarativeNetRequest API which lets extensions modify and block network requests in a privacy-preserving and performant way."[0] MV3 went live earlier this year so you can build on it now, but no word on when extensions will be required to migrate.
Manifest v3 has been widely criticized [1] for weakening ad blocking which of course aligns with Google's self-interest. It's a tough balance to strike.
[0] https://developer.chrome.com/docs/extensions/mv3/intro/mv3-o...