Work (verb): "be engaged in physical or mental activity in order to achieve a result; do work."
No mention of compensation or pay.
For your nurse example, I know nurses that would absolutely do it for free, they enjoy working with their patients and helping them.
For me, I work in IT, if I didn't need to make money to live, I would still do what I do without pay, simply to help others with their complex computer problems.
Just because you don't "get" it, and/or, can't understand it, doesn't mean it isn't something that many of us would take on. A lot of blue collar workers and even many white collar workers (especially non-owner/non-management types), just want to live a life that they can be proud of. We need to earn money to pay for the things that allow us to continue to live, but beyond that, couldn't give any less of a shit about money.
Your world view is flawed, your understanding of the collective consciousness of workers is incorrect.
The jobs that would have nobody working them, would be jobs that are generally horrible to do. Especially toxic work environments, usually due to bad management. Making people's lives horrible because you treat them like trash would be a death sentence, because if people don't need to work for you to live, and you treat them like human garbage, then you will have nobody working for you.
These principles are pretty well founded. There are communities that have survived with little to no money or transactions happening (mainly only when dealing with outsiders), where members of the community do some sort of work for the community (maybe farming, plumbing, electrical, construction, etc) with no direct compensation, and in return, they gain all the benefits of the community. Hot meals, a warm home, etc.
These communes have existed, usually they're associated with extreme isolation and other such conditions, but they take care of eachother without the need for any monetary system.
In many first world countries, the USA especially, people are isolated from eachother. Each person is so aggressively independent that a monetary system is basically a requirement to answer the question of "what's in it for me?" In a more community focused setting, you pay it forward at every step. You do whatever work for the people in the community, and the community at large "pays" you back with their services and hospitality. This is not a question, it is an expectation of such members of a community like that.
For my work, my "boss"/manager is basically setting up and managing systems that I can use to help people with their issues, so I can focus on what I'm good at. Aside from the money that changes hands because we all need to pay rent and buy food, our jobs wouldn't change under a system that has no monetary system. There's still a demand and we fulfill that demand as best we can.
We'll never get to the level of community we would need to get away from money systems unless that money system entirely crashes, and people keep doing their jobs for free to make sure that everything doesn't go down with the money system.
Our money system, with the global banks and fiat currency, is basically a bubble. It is obligated to continue to grow or it will collapse. I won't go into detail as to why, since this post is long enough, but needless to say, that kind of system is destined to fail since continual growth indefinitely is an unsustainable system. It's only a matter of time. One decent documentary I know of on the subject, for further learning, is called "money as debt". Take a look if you want to know more about our collective monetary systems. (Most of the world is using the same concepts and ideas in their money systems though that specific one, IIRC, is focused on the American money system)
Your while argument about it still being work is basically what I was driving at, so thank you. You can perform work, without being paid for it.
I would disagree that such things are not scalable. In your mind maybe, since you seem to be hellbent on punishing those that do not contribute. If you're instead more caring and compassionate, and realize that many jobs are little more than make-work (where you're there simply to do thing that otherwise wouldn't be done, especially in a society without currency), then the actual workforce doesn't need to be nearly as large. A huge portion of labor is dedicated to accounting for and compensating others for their contributions. Think about it. Pretty much all accountants, tax adjusters, government jobs relating to dispensing funds for unemployment, retirement, disabilities, etc. A huge portion of the workforce isn't necessary in that context. Oversight to ensure things get finished is still needed, just to ensure that people stay organized working on larger projects, but nobody needs to worry about scheduling or working out how many hours + overtime you accrue. Most shops which currently warehouse and sell products, like grocery stores, all their cashier's and such, gone. Only direct service restaurants need anyone working there for customer interactions. A huge portion of the workforce would end up "unemployed" (with nothing to do), but retain all the benefits of having a job. Food, shelter, healthcare....
People would be free to educate themselves with college or university without the crippling debts associated with such endeavours. They could play to their strengths and do what they love doing, rather than what they're forced to do because they selected a major without fully understanding the job that they would be doing after graduation, and don't have enough money to go back and pick something they actually like doing.
As much as I don't agree with you, I understand what you're driving at. You're stuck on personal responsibility for your contributions, so that people don't freeload along with everyone else. I understand and I accept there will be freeloaders. I'm not angry about it, it's a fact. All I'm trying to express is that I believe that there will be enough able and willing people doing the job anyways, that we would be fine. Taking pride in their local communities, their achievements, the state/region/province in which they live, and the country they live in, to want to make it the best it can be. That motivation, IMO, is enough to keep things going.
Call me an idealistic fool. Think what you want of me. It's fine. I don't take offense. I know it won't happen so the entire argument is moot. The ruling elite class will their hundreds of billions in accumulated wealth won't allow anything to threaten their dominance over our day to day lives. Their ability to tell us where to go and what to do as a function of our "jobs" which are inexorably linked to our livelihoods and survival.
It won't happen, they won't let it.