I would normally agree with you. However, Facebook is notorious for user manipulation. I suspect they are trying to use the larger federated community to stabilise their own. They know they get maximum engagement out of rage baiting etc. Unfortunately, this also tends to turn the community toxic. If the threads community is diluted down by the fediverse, then they can maximize their milking of threads without killing the golden goose.

Unfortunately for us, things will flow both ways. That toxicity will flow into the fediverse. While the system is designed to deal with this, it can only deal with so much. If we give them their fix, then take it away later, by de-federating, there's nothing to stop them jumping ship to us. That sounds great, until they bring the mentalties from the toxic community that meta created over to us. We don't have the numbers, or history yet to cope and stabilise that sort of influx.

Meta is like gangrene, by the time you realise how serious it is, it's spread everywhere and you're already screwed. The only viable response is to amputate early to protect the rest.