I'm guessing you're talking strictly about the Nexus line? Because there's several Android devices that have proven un-rootable thus far, such as most Motorola devices, several HTC devices, and so on.
I realize that there are some consumers that are forced into certain handsets, and those people lose out. But many people buy devices like Galaxy S4s with the expectation to root and fix what they don't like, which is never something Samsung promises. If such consumers vote with their wallets, we'll see more things like the S4 Google Edition, which is what such buyers want in the first place.
I don't see much of a problem here (exception of those people who don't have Nexus as an option for whatever reason).
http://www.htcdev.com/bootloader
From there you can install Cyanogenmod if your handset supports it, a lot do.
http://wiki.cyanogenmod.org/w/Devices#vendor="HTC";
There is not much point in complaining about not being able to root Android devices. Go for a Nexus or shop around. Not sure about Samsung devices -- they are the market leader after all -- so somebody'll have to help me out on that.