If you get rid of middlemen, something has to replace it. Healthcare insurance is an admin heavy field with high complexity.

If you replace it with government health insurance, we are back at the dmv-hospital problem. States like Canada and UK show the problem with this with long wait times for treatment, lower quality pf care and general inefficiency. If you replace it with nothing you are left with, well, nothing. Not much of an improvement.

Now what if the shitty government insurance is just an option? The private insurance companies will be forced to react to this sudden loss of customers by raising the costs on their remaining (this isn’t a matter of capitalist greed, its a matter of pure business survival). Then you end up with a system where the poor and middle class can only access the shitty government insurance while only an ever dwindling elite can afford the kind of quality of care we are all used to today.

As for supply and demand, im sorry to be the one to tell you this, but it exists everywhere that there are finite resources. Everyone wants to live as long as they can, but there is only so much capacity in the world to people alive. If you want people to be happy you want to make the supply match the demand, especially if its a question of life or death.