The difference between hero or primadonna can be environmental. When there are multiple experts for a department/tech stack, you get heroes. If the bus number is one, a hero risks converting to a primadonna.

I find if you hire heroes with different skill sets you can avoid this dilemma. Or don't hire two Supermen. Hire Batman and Superman instead. But if a hero converts to a primadonna then they were never a hero. On the other hand if you're skimping a hero of the equipment and resources they told you they needed from day one, you're the a***.

I agree. I'd add that having multiple experts in competition with each other (due to bad culture, bad communication or even just bad personality) also has the potential of turning heroes into primadonnas.

Environments don't create primadonnas. It's a matter of attitude and maturity. Being an expert doesn't make a person insufferable.

In my experience, insufferable mid-level management can bring out the worst in the best people, and then accuse them of being primadonnas because they are absolutely incapable of any self-reflection themselves.