IMO a major part of the problem is the bare fact that we assume that our unwillingness to really care about the future is a matter of the brain and evolution. Our culture needs to reduce every issue to something that is qualifiable and categorizable according to some empirical study, not because we care about science, but because we need it to exonerate us. We believe that somehow this knowledge will save us, when in fact even the knowledge of impending disasters has not stirred us to action the way that it should. This is because knowledge, by itself, can always be ignored, rejected, and refused. For example, no matter how many cancer warnings they print on a box, people will still smoke. Until they truly believe that smoking is bad for them, instead of just knowing it, this knowledge will make no difference in their lives.
It doesn't matter whether our brain is perfectly designed by bare evolution to think about the future, because it is clearly capable of thinking in that way if we actually will it to. The problem is not cognitive but moral. In the end human beings find it more easy to be selfish, short-sighted, conceited, and self-exonerating, and because of this we don't want to care about the future. Why worry about generations to come when we can live like kings exploiting the generations that are here now?
The solution to this problem is not some kind of further biological evolution. We need to use our cognitive capacities that already exist, and for that we need a kind of knowledge that can actually change our lives.