I don't want my bank to decline my debit card when I have the funds. But I appreciate that they do it as a measure to evade fraud, because I've had that kind of fraud perpetrated on me and, prior to that, it was easy to imagine that it could happen. So a little friction in my transactions is a cost not a benefit of my banking. But the benefit I get from that cost is fraud protection.

Same thing applies here. If crypto were, on a measure, as fraudulent as it was not, then this might be heavy-handed. But as it is currently the source of more fraudulent activity, at least as it concerns these banks, than forthright activity, I'm happy for my bank to toll the cost of preventing crypto financial exchanging, for the benefit of fraud protection.

YMMV, of course. Different strokes for different folks. But, like the parent commenter, I'm happy with how my bank purports to handle crypto transactions.