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)