The problem with fixed subscriptions in this model is that the service has an actual consumption cost. For something like internet service, the cost is primarily maintenance, unless the infrastructure is being expanded. But using LLMs is more like using water, where the more you use it, the greater the depletion of a resource (electricity in this case, which is likely being produced with fossil fuel which has to be sourced and transported, etc). Anthropic et al would be setting themselves up for a fall if they allow wholesale use at a fixed price.