I don’t even think their goals are as linked as you think,and neither were so altruistic— I believe you’re mistakingly correlating them retrospectively, whereas, in their own times and goals, their actions were notably different. And the first thing you need to understand is that neither of these guys wanted anything but to serve their own interests first. Bettering humanity - let alone anyone else - was hardly on either’s mind— ever.
They were only ever serving themselves and their own desire for power and conquest. When they failed and lost the Eugenics Wars, they fled to space in their cryoships.
We can only speculate what happened to the descendants of Arik Soong between the 22nd century and the 24th.