It certainly puts a dent in to those not doing anything illegal or wrong and seeking privacy.
You can't have privacy while using a bank. I'm sure the bank doesn't care (as banks are generally evil), but they care about the fines they'll get. So they ask you anything they can think of, so they're on the safe side.
Just because they ask, doesn't mean that you have to answer.
I mean that the law (in any country at least as far as I know, correct me if I'm wrong) does not allow them to ask whatever they want and of course, it gives us the right not to answer questions that do not relate to a specific issue.
Have any of you guys been asked by your bank about the source of funds in a recent transaction where you sell your bitcoins (or other crypto) and receive a wire transfer? Especially since the other trader is basically a stranger to you for the bank's purposes?
Basically, no bank can know without investigating a bit further, where the money comes from and I don't mean from which account or sender but in what way it was acquired. Either you sold Bitcoin or shoes or a car can't know it without receipts/ evidence. The problem for the bank is created when either the amount, or the sender, or the account triggers their "alarm". Eg. the sender is blacklisted in their lists, when your account type doesn't justify the amount that you received, more than the usual transactions/ value of them, etc. Don't forget as well that depending on the sender's country is also a very good reason for the bank to ask how you got that money...