LeBlonde didn't say that multiple devices aren't necessary, or that they are trying to rid the world of them. All he said was that they question the need to carry around both a tablet and a laptop at the same time. There was nothing about mobile phones, desktops or anything else being considered unnecessary.
I tend to agree with him. I have a Windows tablet, that is almost a mirror image of my desktop, with a cover that has an integrated keyboard and I use this just like a laptop, but I also use the tablet on its own for other uses. It's versatile, functional and effective. I also have a notebook that no longer sees the light of day.