> Without training cost you can infer only the marginal cost of serving this kind of models.
Which is by far the most interesting number of the two.
> Moreover, you don't know the actual size of closed models (what if Fable is a 10T model? What if it's 1T?)
If you get close in output quality, then does that matter?
> If you get close in output quality, then does that matter?
When you're trying to estimate/infer the costs of serving the tokens and even include the cost of training the weights in order to output tokens then yeah, why wouldn't that matter?
That only matters if you are an investor not if you are a consumer.
Well, or if you're participating in a discussion on HN where the sub-topic happens to be "if labs are subsidising tokens on API pricing" and literally the cost of serving the tokens is relevant to the sub-topic people are trying to discuss...
Consumers want better models too, of course it matters
> Which is by far the most interesting number of the two.
Only if you don't have to continuously train new models, and you are not at a runway risk.