You clearly have not yet witnessed the bad parts of Facebook and Twitter. I've seen people calling for genocide on Facebook under their real name and that's not even remotely the worst.
Facebook's content moderation teams are basically getting PTSD[0] by default as they enforce rules that specify under what circumstances photos of things like animal abuse or decapitation are acceptable(!).
The assumption that people behave normally on the internet when they're not anonymous is provably false. You might think that intuitively, but that's because you're a decent person.
[0] https://www.cnbc.com/2019/06/19/facebook-content-moderators-...