Gravitational waves may have made human life possible

I find the title inaccurate and clickbaity. It was not the gravitational waves that made life on earth possible, but the heavy elements as a result of star collision and star collapse. But we've already known that for a long time.

The referred paper just makes the case that most of the iodine and bromine on Earth must be created by neutron stars collisions and not by supernovae as previously thought.

The paper seems to say that gravitational waves cause neutron stars to collide.

Isn’t it the other way around? (A collision emits gravitational waves)?

https://arxiv.org/abs/2402.03593

It’s always sort of weird to state something like this, because clearly any tiny change to the parameters of the universe would have had an enormous cumulative effect over billions of years, dramatically changing the conditions that led to human evolution. One tiny pebble hitting our atmosphere, or not, three billion years ago, would be a hell of a butterfly wing.

On the other hand, can we confidently say that the presence of iodine and bromine is necessary for the emergence of intelligent life? Can we even say that it makes intelligent life more likely, rather than less? Evolution tends to make use of the resources that are available, but that doesn’t mean it wouldn’t stumble upon alternative solutions if they weren’t.

So basically... causation caused us to exist?

Is there a gravitational equivalent of a 'rogue wave' that sometimes happens at sea?