IIUC, contactless payment via apple pay does have a secondary card number of sorts that's linked to your original card.
I once accidentally paid for AppleCare with apple pay (a mistake), so when at some point I switched phones I had to get new secondary card numbers tied to my physical cards. The old secondaries went away when I wiped my old phone, so AppleCare was no longer able to draw the monthly payment. The number in the invoice was likewise not the original physical card number, but some other number.
Whether the secondary numbers are easier or impossible to track is certainly a question, but I believe there's always a number.
Yes, correct! If you check out https://ghostty.org/docs/config/reference, the iPreviousCursor is available, so it can be used against the iCurrentCursor to produce a fading effect. But I think the entire previous framebuffer isn't there (yet).