Update: Apple now supports exporting as a CSV natively, so I now 100% do not recommend using the tool listed below. I'm leaving it here for postarity, but please just use the native export option in the Wallet app on your phone.
It’s still crazy to me that this doesn’t just work out of the box, but CSV.WTF finally gives you a way to convert the PDF from Apple Card to a CSV so you can do things with the data.
I should be up front that this does require you to give access to your statement to a random website on the internet, and despite the developer saying it all happens in browser, as well as a quick peek at the source code by me, there’s inherent risk in using a site like this with your private data. It seems okay, but Apple should really let you do this up front and not rely on this existing.