They've been saying this since The Computer Chronicles era of the 1990s (the program even mentions the slow down of computer buying) but an awful lot of people still buy and use computers.
"it is the end of the PC" or "Windows 8 killed the PC" or more recently "is it the end of the tablet" because sales are slowing down, are all good sensational statements for click bait articles, or to support personal agendas, but they conveniently avoid to use basic common sense while examining market forces.
You use to have no choice if you wanted to do any types of computing, than to buy a PC (apple windows ....)
Up to not so long ago, the gain in performance every year made a clear difference in how much you could accomplish with these devices to keep up with new offerings like streaming online videos.
So during that time, the PC market sustained a certain pace.
Then Portable computing devices appeared (smartphones and tablets) that could do more and more of the simple stuff people used to need a traditional PC for. So guess what.... A big chunk of the population now have more choices to cover their needs, beyond a traditional PC, and so that reduces the demand for these PCS.
At the same time, even though PC performance keeps growing, the use for that performance is less and less important, at least for a large percentage of users. Combined with increased reliability, it naturally reduces the rate of renewal, and therefore also contributes to the slowdown of PC sales.
So you can either turn the slowing down of PC sales into a sensational statement that the PC is dying, or you can simply acknowledge that the sales of these devices is just adjusting to a slower rate, reflecting the new range of devices available.
Same goes for the somewhat ridiculous "the Tablet is dead" that we heard recently when the sale for this device slowed down.
A few years ago there was no tablets period. Then the tablet was born and proved to be a useful device that could fill the needs of a large group of people. To go from zero to getting the target customers of the whole planet equipped takes a few years. During that time, you naturally see healthy and sustained sales. But once pretty much everyone who needs one has one, guess what happens.... Sales slow down to a lower level of mostly renewal.
All these devices have a use, and as power progressively becomes less relevant for average use, size and form factor is what drives the user scenario. When mobility is more important you use smaller devices, when screen real estate is more important you use larger devices.
So I don’t think any of these devices are dead or dying, their market share is just shifting based on a broader availability of device choices.
By the way, a PC is a Personal Computer, smartphone tablets, laptops, desktops all are Personal computers. They now come in different sizes and form factors, and so far all the known form factors have a useful differentiated target usage. Several of these devices are still young and so the market has not stabilized yet, that is all