I've known many people that worked at FB/Meta, though most of them served between 2010-2020. The scale they deal with does lead to some very interesting tech challenges that can be very satisfying. Most of them eventually moved on, and my impression is that the culture really has changed post-covid.

I visited a former colleague at the Palo Alto campus in ~2014. What they were working on looked intriguing (I signed an NDA to visit and don't remember the terms, so I won't say what), but it did feel cultish at the time.