As a single user, it doesn’t really, but as a SaaS operator I want tractable, hopefully predictable pricing.
I wouldn’t just implicitly trust a vendor when they say “yeah we’re just going to charge you for what we feel like when we feel like. You can trust us.”
Ultimately if the output of the model is not worth what you end up paying for it then great, I don't see why it really matters to you whether OpenAI is lying about token counts or not.