The harsh reality of staff/principal engineering positions is the number of opportunities. There are a handful of companies that are big enough to have roles beyond senior engineers. In those big corporations, there are a few roles available and they are rarely open. Therefore, moving from one company to another is just so damn hard. There are more senior manager/director level roles than a principal engineering role where you oversee multiple teams or a department. If you want to make it to management, your best bet might be your own company or a startup. Happy to hear about your findings.