Definitely a tragedy of the commons or first mover disadvantage situation we have here: systemically it'd be better for everyone to discuss their salaries, but individually I'd never be the first one to start that discussion.
But all this is actually in the interest of the people working there. They may get higher salary and better work somewhere else.
Scenario B: They make more money than me, I (despite my best intentions) slightly resent them.
Beyond that, I’m not really in an industry where you can easily/beneficially jump ship to another firm, so I wouldn’t even have any recourse if people are making more than me without good justification (superior performance, etc). I’d have to exit the industry.