The issue is very challenging, but it needs to be solved regardless. IMO, the key to do it right is transparency.

For example, reddit does that, and unlike FB they’re not afraid to talk to journalists about their content policing, see e.g. https://news.ycombinator.com/item?id=16569778

A quote from that article:

Melissa Tidwell, Reddit’s general counsel, told me, “I am so tired of people who repeat the mantra ‘Free speech!’ but then have nothing else to say. Look, free speech is obviously a great ideal to strive toward. Who doesn’t love freedom? Who doesn’t love speech? But then, in practice, every day, gray areas come up.”