There's an exception for every rule.
As a manager I've fought HR to get pay rises during pay freezes. And won.
Bad managers roll over when presented with obstacles, great ones fight for their team.
I think this is an often missed point. The managers are often just as overworked as the employees but have to handle negativity from 2 directions, both their employees and their managers. They are just people and often their hands are tied due to company policy. They are often just cogs in the wheel as much as we are.
Pushy, bossy, extroverted, or "people person" managers do that. The whole thing is stacked against docile introverts, no matter how many reasoned and well thought out arguments they make.