Yes, of course we would need more IT people, but see, here is the problem: The kind of labor machines and computers will do, will mostly be work of people with lower educations. Assembly-line work, construction, shop assistant, these kind of work. (I know there are exceptions, like machines doing surgeries, etc.) While IT people usually have a university degree or at least diploma. It's usually the smart people who have these jobs and usually these are the people who already get paid well (with exceptions: See starkad...

) and don't have problems finding a job. But what will all the people with lower educations do? The ones who do the "dirty" jobs? No Assembly-line worker will scream "Hurray! I don't have to do this shitty work anymore, because now a machine does the job for me" - Because it means he has no job and therefore no money. We can't all be IT people. I know I suck at it, because it requires way too much mathematical thinking and I was never good at it.
When I read about things like Amazon trying out shops without actually any people working in them, it kind of scares me, if that's the future. It means Amazon and other companies will get richer as in the long run machines are cheaper than people, but what will all the people in this line of work do? Unemployemnt already is such a big problem, it will get even much bigger in the future. One day, unless you are a genius, you won't be able to get a job, because all the simple jobs are done by machines.