Found a bunch of synthetic user stuff to explore...
https://www.enumerate.ai/blogs/syntheticUsers/
https://www.linkedin.com/pulse/traditional-personas-dead-meet-synthetic-joe-johnston-6u8be/
https://github.com/google-research-datasets/Synthetic-Persona-Chat
https://www.syntheticusers.com
https://synthetic-humans.ai
https://towardsdatascience.com/creating-synthetic-user-research-using-persona-prompting-and-autonomous-agents-b521e0a80ab6