Asklemmy

As a species, homo sapiens have managed to adapt to every environment on Earth. We are the first species to have any measure of control over the natural forces which have wiped out countless other species. Diseases which once ravaged our populations are now gone or minor inconveniences and we continue to find new ways to mitigate the worst effect of many diseases. Should a large asteroid be heading our way, we are the only species which may stand any chance of diverting it or mitigating the long term impacts when it does hit us. While it was certainly not a "choice", the evolution of higher cognition, problem solving and intra-species communications has put our species in a unique position of having a high degree of control over out fate. Sure, it has its downsides (we are the only species which might be able to end all life on Earth), but it's been a pretty amazing run for us. On the balance, I think we're in a much better position to keep going as a species than our ancestors or cousins (homo erectus, homo hablis, neanderthal, great apes, chimpanzees, etc).

So, was it a "mistake", I think the current state of evidence is against that. While it may result in a really shit deal for individuals of the species from time to time, as a species I think it would be silly to consider it a mistake.