> Who is paying $99/month if not developers?

Corporate companies. Bog-standard office workers don't need top-of-the-line Mythos intelligence, just something to add to Google Workspace. I personally doubt developers use Gemini for coding beyond marketing materials.

The vast majority of Google's Ai users pay nothing and are not interested in paid plans (yet?), they remain the product.

There is another subset in the Google Workspace for enterprise clients.

Not OP but their Cyber model is decent and already used by Wiz (now a Google property) as well as Armadin.