It seems if anyone wants, they can really gas a model up in the moment and back it off after the hype wave.
Also thinking time means more tokens which costs more especially at the API level where you are paying per token and would be trivially observable.
There is basically no evidence that either of these are occurring in the way you suggest (boosting up and down).
It’s the same pattern everywhere around the world (perhaps there are a few exceptions). Businesses can be much more creative with tax evasion as well.
Businesses don't pay taxes. People do. Every dime that a corporation pays is a reduction of capital returns to shareholders, or a reduction of investment into business activity, both of which are taxed again by the people who ultimately receive the capital.