How is the WiiU a step backward from the travesty known as the Wii? It's an improvement in every way.
The tablet controller not only is comfy as ****, but it's a much better gimmick than stupid motion controls, I welcome it with open arms, all it needs is games so I actually have the desire to buy one. Not to mention it's the only of the 3 new consoles to have backwards compatability.
Also, to answer your Q of how come all consoles don't have backwards compatability, it's because to do that, you gotta do one of two things. Stick the old console(s) in there alongside the new one and mesh them together into one so they work (which is expensive as ****). Make an emulator on the console that can play the old games which is also complex and expensive.
Reason being is because all consoles have different architectures especially from generation to generation, so it's not as simple as just "not taking it out" it's a HUGE ****ing effort, cost and investment for something that's more of a niche thing really. Stop and think, does Windows 7 let you play Win95 games? Last I heard you gotta create this HUGE ****ing loophole to get it to work, and Windows is much more open software than console OS (why is it closed OS, to avoid the crash of 85 again).
Stop being so entitled.