&gt; <i>experts predicted that computers would gain human-level ability around the year 2050, and superhuman ability less than 30 years after</i><p>That is such a weird estimate. Once AI reaches human ability, it will take a few hours-days at most to improve itself to become superhuman. And then it will rapidly approach  singularity in a few hours more. Only a severe limitation of resources or a nuke will stop it at that point. It can probably figure out a way around these issues.