Because it'd give companies like Meta has a strong incentive to stop profiting from it or else people start getting fined/jailed.

It also addresses the problem at (what is often) the source. Police in Ireland don't have the ability to march into Facebook's server rooms and start removing posts, so requests have to be made to Meta anyway which takes additional time. Making Facebook clean up their own mess directly would mean cutting out the middle man and all the red tape and hoops police have jump though to get them to take action.