Pieter Levels has. More than one.

https://twitter.com/levelsio

From his twitter bio:

http://shop.levels.io $8K/m

http://TherapistAI.com $3K/m

http://ApplicantAI.com $0K/m

http://PhotoAI.com $57K/m

http://InteriorAI.com $44K/m

http://NomadList.com $27K/m

http://RemoteOK.com $51K/m

All the profitable uses case I have seen are around AI girlfriends.

I would say the biggest value of LLMs and chat bots in general is making AI girlfriends to serve the people who built them.

My bet is that even those services that see significant usage then have to contend with a large COGS

Sound of tumbleweeds