Seems like an acquihire!
I had never heard about them, but for the life of me, I cannot imagine sufficient paying customers: it's zsh/fish, basically. Sharing the settings is not really a $12/month productivity boost. Acquihire sounds likely.
I've been a personal paying customer going on 2 years now. The biggest benefit I get from fig is their "build a script / cli" functionality. With it you can define UI elements like "list all branches" and you have a nice UI sector and then you can string together code snippets using the outputs of the UI elements. So I have some fig scripts that prompt me for half a dozen inputs and then execute bash and python based on the outputs.
Fig has been a godsend for acting as glue for one-off bash scripts that are added to repos.