User data my dude. All of that unfiltered data, and conversations are gold in the data mining age.
The conversations are all open, and anyone can mine them free of charge, as far as I can tell.
Pretty sure all conversations are public, so you can just scrape for free.
They aren't all public. Let us say, instead, that most of it is public. Furthermore, let us consider that publicness, like privacy, comes in degrees (and perhaps kinds).
Maybe in pre-2019 valuations. If anything it’s too cheap now. Probably worth 5-10 times if this was a public company.