Definitely pointless for passports for the reasons already mentioned--you need data from the bio page to decrypt and can't read the chip on a closed passport anyway.

IMO, also pointless for credit cards. Thanks to modern, strong encryption there's never been a documented case of a contactless card being cloned. Even EMV contact chips, which are quite old technology at this point, have only been cloned in research scenarios that would be nearly impossible to replicate out in the world.

One could theoretically run around with a modified payment terminal and try to collect fake payments, but the reason no one does is because the amount of real personal info you'd have to give to get the merchant account virtually guarantees you'd get caught, and the delay in being paid by the processor is more than long enough for most of your victims to catch the fraud so you'll never see a cent. Plus, in 2023 most of us have at least two contactless cards in our wallets or purses, and the reader will error out if it reads more than one card simultaneously.

If you're gonna do credit card fraud without straight-up stealing the physical card, the old ways are still best: skimmers on swipe terminals, dishonest restaurant staff (in North America) and stolen data from merchants. All three are a lot harder than they were 10 years ago, though.