This. I think software development is the best usecase for AI yet. I use it almost daily at work and it's a huge help.

Enterprise customers will happily pay even 100$/mo subscriptions and it has a clear value proposition that can be decently verified.

Revenue should not be confused with profit. The large AI companies must easily be spending more on compute than they're making from a $20-200/mo subscription. In the best case it might break even for the AI companies. There is no way that they're actually earning a profit from these subscriptions at this time.

It's where the revenue is, but it isn't going to be where the profit is. Developers will easily use absurdly large amounts of compute, costing the AI provider a lot more than they receive in revenue.