Sander that might not be necessarily true either, N26 has a product 'N26 You' whereby you "Choose your contactless Mastercard from five colors – Ocean, Sand, Rhubarb, Aqua and Slate" and the color you've chosen does appear in apple pay, but they are all debit mastercards in the backend... now wether they are from the same number block as assigned by mastercard I do not know. this is just a relevant example for this discussion.
So it does seem banks do have a certain freedom in designating the card images for Wallet to Apple, they just have to designate different one's towards the same cardtype.
however,
Sander not a lack of willingness from bunq (although I have no clue whether they want to change it if they could) 🙂
this actually seems to be the case if I look at it from the outside.
those other banks everyone thinks of are bigger in terms of personnel and userbase, so my assumption is, bunq simply does not have or does not want to spend significant resources to designing distinct card images for different use cases.
Also, bunq is one of the companies who really try to alway KISS* when it comes to their products, so keep that in mind 😉
(*Keep it simple, stupid.. https://en.wikipedia.org/wiki/KISS_principle )