I believe this is not the first article I wrote against the restriction of tethering implemented by carriers, some possible phone makers and Google. The idea of most people is, I paid for the 3G / 4G connectivity and why couldn't I use the money I spent for my 3G / 4G connectivity to browse the Web better by linking it to a machine like a laptop that have more functionalities and a bigger screen than a pathetic small screen of my Android phone ?
Why should a users NOT be able to use the 3G / 4G plan he signed up for at his own disposal as long as he paid his bills dutifully and on time ? After all, he signed up for the data plan with his own hard-earned money.
One conclusion I can think of for the carriers is that they want more money thus they would love to force people to sign up for more data plans and restrict tethering to provide connectivity. The manufacturers and Google wanted to have a good relationship with the providers and keep their friendship, thus allow themselves to be subjugated to the whims and wills of carriers.
How open is Android ? Open to a good amount but many parts of Android are NOT OPEN.
Note: My definition of "open" meant that users have absolute control of what they want to do out of the box. To be considered "open", the user must be able to root and tether without much problems and restrictions. The use of hacking as a way to bypass restrictions to tether or root with the fear of consequences is NOT OPEN.