If we are not delivering it now, despite spending more as a % of GDP than anyone, why not?

Because we pay more to providers for services than anyone else. If they reimburse $300 for an MRI, we reimburse $1,000. If they pay $500 for a colonoscopy, we pay $1,200. Etc. We pay actual providers more than anyone else. Not the middle men, not the insurance companies, not the hospital CEOs, not just the people that we find it popular or pleasing to hate. The actual providers - the medical people who are providing the services get paid more.

You are right in your surmise only if you expect to leave the parasites in place, adding universal care on top of the money wasted on useless middle men and robber baron hospital CEO's, (who write their own pay packages), and let Pharma decide what they should be paid for their products, (often developed at tax payer expense).

No, that's wrong. Because it's not about the parasites. They don't take enough from the system for it to matter. They're the analogy to the "waste, fraud, and abuse" that right-wing conservatives like to point to as being available to allow tons of tax cuts without cutting service. But just like you can't cut federal spending meaningfully without actually cutting the stuff that federal spending actually provides, you can't cut health care spending without cutting the money you spend on actual services performed by medical providers. And if you're not going to reduce the amount of health care services you buy, it means you have to drastically cut the price you're willing to pay for those services.

But I assure you I am right, that we can easily afford care for everyone, ie universal, with the dollars already being spent.

I agree. It just requires giving everyone in the health care industry a substantial haircut. Not just the parasites or the people that it would be politically palatable to damage economically. Everyone.

Which is why it doesn't happen, and won't happen.

It has nothing to do with whether this is tooooo socialist or not. You can't substantially expand the amount of health care services that you provide without substantially increasing the amount you spend on health care unless you reduce health care reimbursements and prices to the whole system, and not just the "bad guys" in the system. That's unpalatable for progressives who want the world to be different than that, but that's what killed all of the state efforts. Even in the progressive states where there was plenty of political will to adopt single-payer. They couldn't make the dollars work.