It's pretty stupid because as others in this thread have pointed out it's already not a flat plan. Even from their side it makes zero sense to bill things this way rather than based on usage. It's not like a VPS where your VM shares the hardware, which consumes electricity more or less regardless of what you use the machine for.
The difference being that an LLM request is not an operating system. Since they're compartmentalized and ephemeral, you can very easily distribute requests among your available hardware so that you can switch off machines during periods of low activity.
But that would be using (a special Claude code version) of the API; as it stands now, I have tried the current api for fun and I hit $200 well within an hour. So if they would charge for real use, no one would use it as there are competitors who have less harsh limits with tier plans still. If all go away then I will be running open models on vast.ai or so as those are now viable (been testing with glm 5 and it's great for coding). So tier subscriptions cannot go away as it will end those companies fast.