You might want to distinguish

• Wishing that person X would behave otherwise
• Being glad if person X suffers
• Believing that making person X suffer will cause them to behave otherwise
• The world will be a better place if person X would behave otherwise
• The world will be a better place if person X suffers

Plenty of people seem glad to hear about other people suffering regardless of whether it has any plausible chances of causing behavior change. Just look at any countries that hate each other (Japan vs. pretty much the rest of East Asia), political opponents ("far-blue political leader breaks his leg; far-green partisans celebrate!"), etc. Your case here doesn't seem particularly different.