Ransomware won't stop even if you don't pay up. Just destroying the target by data loss can be a sufficient reason for any attacker. No payment needed.

This is wildly incorrect. For criminal groups who intend on making money, that payment is needed on a certain subset of victims are they can’t stay in business.

I am a shady company who wants to take down a competitor. I can hire a hacker who'll do the dirty job for me and then get paid in cold hard cash. Or a nation state actor can decide to attack an enemy country's infrastructure.

So? If their goal is destruction what does that have to do with ransomware? They can do that whether paying the ransom is legal or not.

Deception? It can confuse the target about the motives of the attack.

So they were going to destroy data anyway, so this isn’t what outlawing ransom payments is meant prevent because it can’t. It will prevent ransomware for profit if no one pays.