This article seems needlessly mean and poorly researched, like you just vaguely skimmed the Kickstarter pages rather than actually reading them thoroughly. Lots of reductio ad absurdum (oversimplifying and rewording someone's argument with the intent to make it appear ridiculous) going on here. It's almost like 15 minutes isn't enough time to get a full sense for the content and value of 6 different Kickstarter campaigns. What a shock! Even as a throwaway joke article, there are surely better ideas you could've come up with than mocking some actually decent-looking projects.
The first one seems like it fixes something that the iPhone is severely lacking, and one of the biggest things I like about Android phones over the iPhone. Adding a dedicated "back" button adds an extra element of user-friendliness to the device, and at the very least can't be a bad thing.
I actually quite like the idea of the headphones. They seem to address the main problem with using headphones - that is the way they compromise your situational awareness - while at the same time fixing a secondary problem I have as a glasses-wearer of my ears getting squished against the arms, meaning it can be kind of painful for me to wear headphones for extended periods of time. By having a wider point of contact with the user's head and going over the ears, these headphones look like they'll help with that too. As for people around you being able to hear what you're listening to, they posted a video addressing that concern. If it's accurate, it seems like (at least from the front) the noise leakage will be comparable to conventional headphones. The demonstration they posted wasn't exactly exhaustive, but it looks like that won't be an issue.
Those socks look like a nice idea. Seems like they'll prevent your feet from smelling bad after a day of wearing shoes, which would be nice. Cute marketing, too.
The back thing isn't a bad idea. Bad posture is unhealthy and can lead to back problems, and as someone with bad posture myself, I can see how it could be helpful.
There are probably uses for the USB on/off switch. None come immediately to my mind, but I can imagine how other people could find some for it. Considering it's only about $5, it's not bad.
I don't have any particular use for the sweatband thing either. I don't work out or spend time in high-temperature environments, so it doesn't appeal to me personally, plus I don't sweat as much as most people. However, for people who do, and for whom sweat under their clothes can be a common problem, I can see this being more appealing than an undershirt, which would trap the heat and ultimately make your problems worse, this would absorb it without the added layer of an undershirt. Again, not useful to me personally, but I can see the value in it.