Not just "just use 1Blocker", but isn't the mechanism 1Blocker uses functionally equivalent to the "old" mechanism? Whereas Chrome just turned it off without offering a different route to the same functionality?
Chrome does not to my knowledge provide an API like this, and extensions are still roughly a JS bundle that defines blocking rules at runtime, slowly, using more energy, and potentially having access to your browser history while it does it.
Chrome has not changed how extensions work yet. That's all in the future. Currently, nothing has been turned off and the "old" mechanism still works. Eventually that will change, just as Safari has already done.