Great idea, but I think still very specific to very few users. The bunq app already alerts when you try to make a transfer from a savings account, so it could add the same alert when you are linking a card. Easy and lightweight. And if you don't want to see the account, simply drag it to the very bottom :-) Hiding the accounts would certainly cause confusion to some. I can see someone hiding an account by mistake and then going nuts on support saying the account is gone... 👀Maybe a better approach would be to introduce a Favourites section for accounts, so you could only mark your daily budget and other accounts that you want to track on a daily basis to appear on that particular view.
One of the things I like about bunq is that the app is not cluttered. There are tons of ideas from users and if they start adding every single one of them it will become a big complex mess. And let's not forget about the API - all these ideas can be implemented by 3rd party devs, if you make a good case for it I'm sure someone will take on the challenge :-)