These numbers are realistic for any senior engineer working there for over 3-4 years.
I work hard when I'm at work, and really focus. I don't do a lot of the extra-curricular stuff that you can easily spend your time on. I'm an L6 and last year earned just north $450K with decent performance reviews. I have damn near a million dollars in unvested $FB RSUs, too, so there's almost no chance I'm going to leave for anywhere that won't match that with equally liquid public shares.
¯\_(ツ)_/¯