Possibly not, but multiple Chromium-based browsers have already built their own adblocking solutions as part of the browser itself, so they certainly don't have

Possibly not, but multiple Chromium-based browsers have already built their own adblocking solutions as part of the browser itself, so they certainly don't have to care. Brave's especially is about as strong as uBO, Vivaldi has a decent adblocking system and the people making Arc are looking to build their own as well.