They already do for big services. Thats why its called a preauthorization. It just doesn’t work well in emergencies and they dont do it for shit like routine blood draws. Ive had them tell me I could get a CT now and hope they approve it or take my chances. There is still incentive for the provider to fight the battle because patients getting big bills often don’t pay them at all (it helps if you tell them though, they are busy and not necessarily keyed into every patients bill status).