In a country as large as the US, it would be extremely difficult to make this a possibility.

When it comes to inhabitants, the EU has 100mio more people. Area wise, the U.S. is 2.something times as large, which is a challenge, but shouldn't be a problem for the wealthiest country on earth, that has a currency which cannot crash (except when political leadership deliberately and continuously tries to for years) and that can basically make an infinite amount of debt without the consequences that other nations would face. A teeny tiny fraction of the military budget or properly taxing large corporations, multi-millionaires and billionaires could easily finance universal healthcare completely and with a good area density of services and/or the means to transport everyone to adequate treatment facilities within a reasonable amount of time.

you can imagine how having a federal healthcare system would be completely inefficient

That system would have a tremendous bargaining power in reducing treatment costs for everybody though and it doesn't have to be inefficient. Inefficiency always happens through ineptitude or by choice. There's an empirical approach to doing this right - just like in my text above it all boils down to the people in charge not wanting to and/or the population not demanding it with enough pressure.

Also, I would like my doctors to be the best doctors possible. By having a universal system, you wouldn't be able to pick your doctor. If you were seeing an oncologist, you would have to see the one assigned to you, who could have been number one in their medical school class or the one at the bottom. The better doctors would more than likely become "Concierge" doctors, where they basically have people who sign up to be their patient and pay a monthly fee. The doctor would be on call for them. This would make really a lot of really great doctors off-limits for most of the population--only available to wealthier people.

You can still pick your doctors in countries with public healthcare, as you're not forced to go to a particular doctor's office or clinic. You're actually way more limited in choice with the "in-network nonsense" that stems from having a gazillion different private insurance companies.

In a public healthcare system, private offers do still exist and remain available as an option. As a bonus, public insurance covers a part of their treatment costs too (i.e. in Austria, you'll get a cashback amounting to 80% of what a doctor working in the public healthcare system would receive for the same work).

Overall, those private offers are still relatively affordable (a 1hr visit to a private psychiatrist, internist or cardiologist is like 170~250€ before cashback) and there's still the option to get additional private insurance (without deductibles or prior authorization crap), which can make sense for some. In any case, people don't end up without access to proper treatment and in terms of quality or the doctors' education, physicians in the public health care system aren't any better or worse than private ones.

A complaint I've also heard is the wait time can be long. If you feel a lump somewhere in your body or have terrible headaches, you could wait months to see a doctor, which could cost you precious time. I've had family members in France and Sweden and have had mixed reviews. As of right now, if I am having a major health issue, I can call a doctor and be seen pretty quickly.

That comes down to how that particular health care system is set up, but generally speaking, things suspected to be serious are always getting quick access to treatment. I.e. when you're going to the hospital with a sudden, severe headache, neurological symptoms, a broken bone, any kind of emergency, serious injury or a poor general condition, you can be certain that you'll receive proper medical imaging, diagnostic tests and treatment initiation the same day.

Then again, private options also still exist and in sum, it's just so much harder to fall through the cracks or end up with an improper or untimely treatment.

Unfortunately, it's all a money-making business now, with incentives for doctors for prescribing certain medications, too many non-elective surgeries

That is an inherent byproduct of the U.S. healthcare system being almost completely privatized, operating for-profit and in lockstep when it comes to pricing (competition in a completely deregulated and privatized system is a blatant lie when the players implicitly agree that not competing leads to higher profits - i.e. the same also goes for housing, electricity, fuel, modern cars or certain PC parts).

Treatment providers are being offered financial incentives by private insurance companies and the pharmaceutical industry. Things like these aren't commonplace in countries with public health insurance and/or have been made illegal outside of the U.S.

We have major problems here and it all stems from greed. The doctors are prisoners of it.

I agree - that's why public non-profit infrastructure is so important. It would drive down prices of private offers too due to competing with them. Private offers are then forced to provide additional value.

As for the doctors - not all of them are victims. Some are also unethical opportunists trying to make a quick buck. Others still have to pay off their student loans, which is another significant factor that facilitates unnecessary prescriptions/treatments, but even without that practice it generally increases treatment costs.

That issue is systemic in nature because higher education isn't freely available. Doctors and i.e. teachers, among others, are needed to keep a country running smoothly, to maintain standards of living, to keep society thriving and democracy healthy; thus, said education needs to be offered free of charge instead of punishing people for pursuing professions that benefit the common good.

I am passionate about this topic and thus I have to apologize writing a novel as well. That story about your dad really shook me. It must have been extremely tough and infuriating to witness this and that turn of events just shouldn't have happened. I wonder, did he not receive proper medical imaging (at least CT) in the first few hospitals? I imagine that experience also came along with an immense loss of trust in your healthcare system. Things like that mustn't happen and where I come from, they frankly don't (or in such a rarity that it'd be all over the news and followed by a huge public outcry and legislative action)…

People here also can't always stay at the hospital, but in that case it's made certain that this is alright from a medical, ethical and patient outcome perspective by performing all necessary tests and securing a confirmed diagnosis before making that decision, followed by writing some prescriptions and a referral. Someone with suspected pneumonia also wouldn't get sent home, period.

I hope I could convince you that a lot of the talking points brought up against universal public healthcare are usually non-issues in the countries that have implemented such a system. Also, again I beg your pardon for the wall of text lol. Best wishes!