This is kind of a straw man. These valuable data sets are typically kept by tech companies to keep a competitive edge. For example, not even Google sells or rents user data.
The more relevant question is "is Stripe's valuation significantly predicated on revenue it can extract from the surveillance data it's collecting?"
My guess is that the answer to this is likely yes. Fraud prevention is the current product built on this data. But it would be shocking if the company never put the data set to additional uses.