Recent report says there are 1M paying customers. At ~30USD for 12 months this is ~3.6B of revenue which kinda matches their reported figures. So to break even at their ~5B costs assuming that they need no further major investment in infrastructure they only need to increase the paying subscriptions from 1M to 2M. Since there are ~250M people who engaged with OpenAI free tier service 2x projection doesn't sound too surreal.