Good Enough Technologies

Is there a level of technology that is "good enough", or will we always demand faster, bigger, higher resolution? The following technologies' successors aren't doing too well, which might be an indicator that they've reached "good enough" status:

• iPhone 4 - if you don't listen to Apple and look around, a lot of people are still using 4 and 4s. Probably because the 5 doesn't have that many more features, and the 4/4s are already very good.
• 802.11g - 802.11n is a mess.
• Windows XP - still in demand, actually.
• USB 2 - most devices sold are still USB 2. USB 3 ports are listed like they're an optional feature, not a necessity, like power steering on rental cars was.