A person (or a company) can be two very different things at the same time. It's undeniable as you say that there have been a lot of high-profile open source innovations coming from Facebook (ReactJS, LLaMA, HHVM, ...), but the price that society at large paid for all of this is not insignificant either, and Meta hasn't meaningfully apologized for the worst of it.
Meta’s open source contributions stand on their own as great regardless of their obviously shady social media management and privacy tactics. The former are feats of software engineering, the later have a lot to do with things far beyond problems like handing data at scale, refreshing feeds fast, ensuring atomic updates to user profiles, etc.
Basically I don’t think their privacy nightmare stuff detracts from what the brain trust of engineers over there have been doing in the open source world.
