Then why is Medicare being able to negotiate drug prices instead of being required to pay the list price such a big deal?

I forgot about that. But I don't think it's that big a deal, because for other things, they already set the price:

"The prices that Medicare FFS pays providers are set administratively through laws and regulations, and providers can either take them or leave them."

https://www.cbo.gov/system/files/2022-01/57422-medical-price...

And in 2016 only about 10% of health costs in the US were prescription drugs.

https://www.actuary.org/content/prescription-drug-spending-u...

They're arguing that the USA doesn't do that, but should.

"The prices that Medicare FFS pays providers are set administratively through laws and regulations, and providers can either take them or leave them."

https://www.cbo.gov/system/files/2022-01/57422-medical-price...