In the future world of SDN and automation, it’s true that there will be fewer people needed to troubleshoot basic network problems, as miss-configurations will likely be less common. However, when mistakes will happen, less people will actually know how to spot them and even fewer will actually be able to fix them.
Software always does predictable mistakes, while people will make different mistakes every single time.
When you’re wrong with automation, you break everything, not just one thing.
The most business relevant elements of IT cannot be automated, because they require creativity, vision and architectural savvy.