The pay for principal SWE can get up to $1m+ (at large sv tech companies, or even at startups assuming their equity pans out). That $800k number is more accurate for staff/senior staff.
All the principal engineers I have worked with have been humble and ego-less engineers. There’s this notion that they just write docs but they’re invaluable code/spec/design reviewers, they have taken on major refactors to tackle tech debt that just lingered for years, and have generally unblocked me on so many occasions. The strongest principal engineers have never taken credit for massive projects they have orchestrated but “everyone knows” they’re valuable.
It takes a lot of skill, and I’ve found they switch between the “archetypes” effortlessly. Beyond that, they’ve helped me grow in my career and find impactful projects that look good on perf reviews. In my mind, the good ones are definitely worth their cost.