Not the worst, but that's a low bar
Pros
Working at global scale, Meta has to solve some unique problems few other companies have the opportunity to see. Meta will often be at the forefront of new technology, or sometimes is creating that new technology, for solving problems. Smaller companies often have to settle for commercial off-the-shelf products that half-work or don't actually properly work, but Meta can do it properly. Your managers will most likely care about you and do their best to support you in whatever you need. Base pay is probably a bit lower than other similar companies, but overall benefits are incredibly hard to beat.
Cons
Upper management doesn't care about you at all. Your immediate managers do, their managers probably do, beyond that it's uncertain, and by the time you get to the VP level they don't care about the individual person. Diversity support is a joke, you're supported as long as you fit one of these very specific predefined Silicon Valley molds otherwise you get support for what fits in that rather small space. Talking about what's wrong is strongly discouraged, there's even a policy that people have fallen afoul of just for criticizing that same policy's impact on discussions about how to improve life at the company! Career progression is less about what you actually do and more about how much a bunch of people think you do. I've done some huge things, well-received by people and still talked about today as a good example of a company-wide high-impact project but got a bad rating, and I've very recently had a year where I did basically nothing all year but made a bunch of upper managers happy and got a great rating. The way multiple layoffs have been handled has left us not knowing whether it's even worth working hard for a great rating anymore since we've seen high performers fired and low performers safe. At first layoffs were held dishonestly, but then subsequent layoffs were held in possibly one of the worst ways to respond to those criticisms.
