I think you are talking about cryptocurrency software evolution. I quite agree with the sentiment. But only up to a point. Up to which point? The point where human biological evolution stopped being relevant because human cultural evolution outpaced it by many orders of magnitude.
Some elaboration may help make this more clear.
It seems to me that if the cryptocurrency software allows for high flexibility of the governance/economics rules which the community creates for itself, then design iterations of these rules can readily happen within the same community. Yes, the biological evolution of organisms (if we use it as a parallel for the design evolution that I think you're talking about) requires forking out (new species created) and leaving the old species behind. You can't achieve the possibilities/behavior of the new organism while retaining the old biology (old governance/economics rules in our case). But, once you get sufficiently complex, like having a highly complex nervous system, then that allows you to readily change your behavior and achieve novel great things simply through learning (no requirement to change your biology).
So, do you think Steem has sufficient flexibility to allow for a continuous evolution of the rules (organized human interaction) within itself? Or does evolution need to happen some other place?