Pay is determined by the labor market.
Substitute wizzle for “senior engineer”, and wozzle for “bootcampers” or “marketing”.
Facebook pays $150k for wizzles because that’s what it costs to get good ones. It pays $110k for wozzles because that’s what it costs to get good ones.
People (reasonably) want a specific combination of wizzles and wozzles, for growth, different roles, etc.
At no point does Facebook assign a price for wizzles based on their expected individual contribution. Maybe there are some “market makers” in some industries, but I don’t think it applies in tech.
Tangent, but did I miss some trend here? Over the recent months, I've started to see the phrase "individual contributor" being used pejoratively, at times almost like a swear word. Is it now a label that's assigned to bad employees or something?
The real point is it's not about what you are "worth" but about your market value. If you are away from Silicone Valley where you could find a similarly paid job, your options are more limited. That's a loss of bargaining power and Facebook thinks they can get away with paying you less.
You may be worth $150k, any one individual engineer could be worth multiples of that!
Look at your entire engineering team, from best to worst. Is not there some inflation of salaries in the SF Bay area? The bootcamper that is making $110k out of bootcamp? Are they really 73% as effective as you?
The marketing person down the hall? Do you contribute more then that person today? Yeah, probably. Without marketing to get the word out and sales to actually bring in the cash, how much would your contribution be worth?
You have to look at the whole system as a manager. And yes we pay the bootcamper $110k because we hope they'll grow into be a great engineer like you.