At first https://twitter.com/theryanking/status/1485784882173255680 seemed pretty damning but if you hover over the dates of the HN posts, the title attribute shows the timestamp, and it would appear Stripe's came in a couple hours before Bolt's. Add in Lyft and the "facts" around this story really seem to fall apart.
Yes, Lyft not being YC is is mostly it but also from an early Stripe employee [1]: "Lyft was also not originally on Stripe. They were on Braintree and switched over to Stripe after both Stripe and Balanced (another YC-funded payments company) competed for their business." Balanced was definitely a payments company also backed by YC. I cannot verify the switching from Braintree as I'm mostly an observer in all this but the other details are easily verifiable.