Its not the patients that lobbies for these laws...it is the insurers, and its to lower their costs.
Its also why the insurers pay the pharmacists a bonus for these changes, if it was about costs to the patient, the bonuses (money back) would go to the patient.
I mean, no, patients don't lobby for them because patients don't really lobby en masse for healthcare policy in general, but patients definitely are the ones who benefit from them.
There are some cases where the relationship between insurers and patients is adversarial. This is not one of them.
Well imagine your doctor gives you a Rx, you go to fill and the insurer tells the pharmacist to ask doctor to change it. If the doctor disagrees (for whatever reason) the insurer may drop your doctor from their network, then you will be stuck going to a doctor who does whatever the insurer asks.
If you feel there is no conflict there or that isn't adversarial that is fine...in my experience both patients who lose their doctor and the doctors themselves disagree.
See Medicare for All.