Just what do neutrons do? My theory is they are akin to atomic fat.
I’m probably the wrong person to ask but, as we know, like charges repel. Therefore, protons would have a difficult time forming nuclei if neutrons weren’t present to give them something to bind with. If it weren’t for neutrons, we definitely wouldn’t be here!
Without neutrons the nucleus of most elements would be unstable. They act as mediators of the strong force that acts to attract protons together and the electromagnetic / weak force that causes protons to repel each other.
For one thing they make the sum of the binding "strong interaction" between hadrons (protons and neutrons) in the nucleus larger than the repelling electromagnetic force between the protons. Which makes stable nuclei possible.