If mostly for one thing: the complexity of the systems. And interestingly enough, a biological virus is not considered a living being, it really is a genetic program code, not much more.
Still, there will never be a robot sitting right across the table, who humanly understands what you are saying, emotionally shares an experience you are recalling or could marvel with you, if what you see as red, maybe for him really is green, just named following the common convention.
More realms of what is deemed intelligence will be seized by computers. But man didn't stop enjoying cycle races, just because cars came along. Isn't it rather astounding, how long it took until a computer played 'better' chess than a human? We are long used to be outpaced in counting and calculating by scientific calculators and — it didn't really feel like a loss. Computers, and increasingly robots, will take over a lot more services in the future and make new things possible. But they will always lack something science is to quick to dismiss, since calculating is not understanding.
They will never share the experience with us.
That dot, sadly, doesn't know what love is. It's just 7 lines of code.
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