I guess it depends - if the miserable conditions and work I was doing only affected me, maybe a couple of years. The problem here is that Meta is a company that actively does harm to the world. They've contributed to genocide in Myanmar, harmed children, and overall have been a net negative on society. So my answer to your question, if we're strictly talking about Meta, is none. I would never work for a company like Meta because I value other humans more than money.