It's not about niceness. When you get a text about a potential scam there's an urgency to reply. And you can't just ignore it. All major banks send out official text messages to confirm large transactions. This has happened to me multiple times with Chase, and just recently I blocked a fraudulent ATM withdrawal using exactly the method outlined in the article (someone skimmed my debit card when abroad, I got a text from Chase when they tried to use it, I replied no, got a call from the customer service rep). Only thing missing was reading out the OTP, obviously, which I would not have done.