Re: not neccessarily very good at brown-nosing...
"One Manager kept marking me down at review time for 'having no ambition'."
At my company, being a manager means working 60+ hours per week (and no Paid OT), any bonuses usually significantly derailed by zillions of uncontrollable external factors, dingy office with no windows, high stress, etc.
They'd need to pay me +50% just to keep the hourly rate similar. But the offer would be maybe +15%. Yuck.
So is it my lack of ambition, or is it their own management structure issue?
This same logical thinking results in widespread "lack of ambition", which impedes progress generally. The negative outcomes are wider than you might think. It's not good.
Senior leaders should really beware of this terrible situation. Not good.