The Wii was extremely popular. For years, it outsold every other console combined by several orders of magnitude.
Netbooks absolutely were overhyped, and the market for them died really quickly. They were barely usable, and by 2010 when tablets really started hitting the market, there wasn't a space for them anymore.
HDTVs weren't overhyped, they were just expensive, and in 2008 there wasn't that much content to take advantage of it. I had a 32" 720p TV that I paid nearly $700 for in 2007. Now, you can gt a 40-something inch 4K tv for a little over $200, and there's plenty of content to make it worthwhile (though the real-world benefit of 4k on such a small set is debatable).
The first iPhone was so incredibly polarizing at the time. The hype machine leading up to that announcement was unlike any other product launch I can recall. So it was never going to live up to that kind of hype. And while it was limited in features for it's time, it was clear more was on the horizon. And given how it not only revolutionized the phone market, but also the web as a whole, we know how it all ended up.