Interesting. Tell me what's the difference with content blockers before and now? Maybe I am. But the content blockers in the past had more control on what to block.
I think what you are discussing is the move to only supporting declarative block lists. Long ago in Safari, and until very recently in Chrome, you could have JavaScript run to check and modify/block requests. The modern block lists still function the same (preventing a Request from ever being sent) just without dynamic code in the loop.