Even Disney couldn't ignore the mass cancellations after dropping Kimmel and Disney+ bearly turns over a profit.
Realistically, you need at least ~1M subscribers to cancel to make this painful.
But I suspect this will get drowned out in the face of other news.
If you back down from using Chatgpt, you throw a wrench in their growth numbers.
I would consider training data could have important info as well and to be honest, with their circular financing, Nvidia <-> openAI with GPU's being the main cost (and given that OpenAI isn't facing the Ram crisis heck it created the ram crisis by pre-ordering 20%) and recent deals, money isn't an issue to them for some time now. Growth is.
You are also forgetting that OpenAI is planning to add ads in which case you would be the product, its better not to discourage anyone who wishes to cancel perhaps.
Other commentators have made some good points as well and I used to think the same thing as you but I do think that cancelling might make the most sense.
That or if you want to cause maximum damage, trying to burn the most tokens that you physically can asking random things to burn OpenAI's money but remember that the model still takes energy requirements so you'd be wasting energy for something quite pointless.
IMO, it might be better to cancel/not use OpenAI.