"A smartphone is used for consumption" is just a bad generalization. Is making calls, sending emails and text messages "consumption"? No. And for tablets it's an even worse generalization. But still, _most_ computer usage _is_ consumption! And most of it that is not (like word processing) can be done by attaching a keyboard to a tablet. The office workers that actually need a workstation (like graphics designers, engineers and programmers) is only a small fraction of the workforce that uses a computer today. Business use is one thing (and changes there always happen a a glacial pace). But my parents and my girlfriend now rarely uses their PC.

They either use a tablet, or their smartphone if the tablet isn't nearby! So the key here is convenience, which incidentally is why the laptop became so popular in the consumer market. When that PC dies, they will take a hard look at whether they really need to replace it.