As far as moving to another country, I have no need to, I make a large amount of money here and can afford the health care bills. I want the change for people that are not as advantaged as I am. I am willing to pay more so that they can get it.
As far as change in the US happening soon, I don't know. I think we are at an inflection point with more and more people desiring a change. People are losing their jobs right now and with it their health insurance. The election will potentially be a referendum on increased publicly available insurance.
The US healthcare system is a mess, I don't disagree. I don't believe there are any cheap & easy options to change it however. The grass is always greener on the other side of the Atlantic, but sometimes that's just because tales of success are spread around the world while the problems stay in the local news.
It also inflates health care cost, because the doctors use the private insurances to finance investments in expensive equipment. Talk to someone with private insurance, they essentially have fight off all sort of unnecessary tests even if they go in to get a flu vaccine. And no not every doctor needs an MRI in their practices. Also many other European countries have functioning health care without private insurances, which disproves the point they are necessary.
I have private insurance, and I've never had to fight off anything. The main difference is that I'll usually get an appointment on short notice and my provider pays for my glasses and good dental work.
And you're absolutely right, they aren't necessary for any system to exist, but they are necessary for this system to exist at this price. If doctors didn't pay the rent with private patients, they'd go bankrupt.
And make no mistake: Germany's public health system works only because of our parallel private insurance system. Doctor's can't run their offices with public insurance patients, because the amounts they can bill are strictly limited per quarter. They make the money they need to survive on the private insurance patients that pay ~2.5 times as much and will pay per visit/procedure, not per quarter.
Of course, this also creates a two-tier system with the private insurances getting the good treatment and everyone else having to wait quite a while to get an appointment, not getting quite a few treatments (e.g. eye glasses, unless you're basically legally blind).
You're on HN, so you're most likely a skilled knowledge worker. You'll be greeted with open arms in Europe. Vote with your feet, give it a try. I don't believe that you'll see substantial change in the US, too many people (regular people too!) profit from the individualist approach.