This is facile, and you certainly haven't proven the absence of free will just bey stating it here.
I believe the best assumption, since we feel as though e have free will, is to behave as though we and other people (and animals) have free will.
But aside from that, the fine article isn't really saying anything new. It's a known thing that anger has a dis-inhibiting effect. IIRC, it bypasses the prefrontal cortex in favour of the limbic system.
This is why so many religions and philosophies (esp Buddhism) warn us about the dangers of acting on our anger.
Anger makes us do ill considered things, and we often harm people and regret it later.
If you believe you don't have free will, it can be easy to excuse all sorts of behaviour, because it was 'predetermined ' anyway.
Sort of like, stealing candy bars from a store then saying, I don't have free will, what can I do? ¯\_(ツ)_/¯
Taking the candy bar example, in current society, even someone who doesn't believe in free will probably won't steal a candy bar, since there's a good chance they'll get caught, and then shamed and fined. There can still be a system of rules without a sense of free will.
The mindset would probably affect every aspect of life, but just looking at criminal justice, my intuition is that we would reduce how retributive it is, and switch to something more rehabilitation focused. Then again, it's hard to imagine what the knock on effects of that would be. I could see it going too far and getting exploited. Still, I'd be happy to see society experiment with moves that direction.