It may be a lot harder than we think. In turn, it may take much much longer than we think. Perhaps we will trash this planet before we reach the point.
But it's hard and we don't understand much at all about us, and the things we built after thinking we had some gigantic insight are kinda not as great as we hoped them to be. Therefore, doubt is appropriate. (as is working on further progress)
We will make humans brains more computer-like instead of making computers more human-like. Some day, the last cyborg will replace their remaining flesh with metal. Strong AI the hard way.
Uh, ever heard the statement that premature optimization makes changes harder further down the road?
The problem with the body/mind system is the insane level of interconnection and feedback loops. "We made you 20% smarter!, uh, sorry about the 60% incident increase in cancer though". The size of the problem space when dealing with human minds is astronomical, we will likely need intelligent systems to solve the problem, which means the silicon Strong AI will come before the Wetware AI.
