Facebook has created a truly toxic environment - it is hyper-competitive. Rarely a day goes by without talk of being impact-full, impending reviews or cross calibration. So much time-effort is wasted on internal posts shamelessly describing improvements (which are often just fixes to your own shoddy work).
Like working in chicken coop?
Beware, role deflation - you will get a pay raise when you join, but, typically, you will be just another software engineer (like any new grad) - regardless of your experience.