It could be Europe has stricter driver's license requirements resulting in fewer people who might succumb to distractions getting behind the wheel. And more availability of walking and public transit options meaning more of those people don't need to drive in the first place. Giant vehicles certainly don't help regardless.
Sure, it could be that.
But when we cast around for other explanations, for some reason it's always interesting to zero in on an uncontrollable factor that means we aren't responsible for the situation we find ourselves in.
Btw Europe is full of the same dumb humans that live everywhere else. Granted, they have better bread, cheese, and health care.