Another possibility is that the hype cycle is deliberately designed. That's also kind of what you are saying: If the hype cycle didn't exist, tech reporters or venture capitalists would probably have invented it.

To a physicist the hype cycle looks like a very slightly underdamped oscillator. [1] It oscillates a bit... but only for one or two cycles. And the pain caused by the "Trough of Disillusionment" is quite possibly outweighed by the utility of that initial steep slope. Or by the risk that, if you try to design the perfectly damped hype cycle, you will err on the side of caution and design an overdamped hype cycle, which is a disaster.

(To translate that last bit out of Physicist: If you try to design a product that is perfectly suited to its intended task, perfectly scalable -- not too little or too much -- and has perfect, clear documentation so that everyone understands exactly what it is for and what it is not for... there's a good chance that you will design something that is ever-so-slightly wrong for the market, and everyone will know that it is wrong (thanks to your complete honesty and clarity) and it will take a little too long to fix (because it's so thoroughly overengineered)... and by the time you get it fixed the quick-and-dirty hack will have stolen your mindshare and your market. Or you'll just run out of money before getting it fixed.)

---

[1] Of course, as Bruce Sterling once pointed out, the cycle is incomplete. Nobody ever draws the right half of the curve, which includes "obsolescence", "death", "consignment to collectors on eBay", and "rebirth as a cool, retro fashion accessory".