Re: There is a reason why I use wired KB's
"Bluetooth range is pretty short. Unless you live in an apartment with paper thin walls, I don't think people could get close enough to your keyboard to steal keystrokes."
What does Bluetooth range have to do with anything? As the article explicitly states, no Bluetooth keyboards were found to have a problem, it's wireless keyboards using various other radio connections that are the problem, and they could have pretty much any arbitrary range depending on what transmitter they happen to use - up to 100m away according to this report.
"As for the mouse, what exactly are they going to learn by stealing your mouse movements and clicks?"
Who knows? Good security generally means you're not leaking information at all, rather than simply hoping the information you are leaking isn't useful to anyone. There are endless examples of people not bothering to secure seemingly innocuous information only for someone else to prove it wasn't that innocuous after all. A recent related example would be using the accelerometer in a phone, often not secured because it can't do anything harmful, to reconstruct keystrokes from a keyboard on the same desk.
Obviously there are limits and wrapping everything in tin foil is overkill for most people. However, deliberately broadcasting all your information in plain text for anyone to see is generally considered something to be avoided even by those who aren't especially paranoid.