Worse, it does not effectively disclaim liability for the software developer. He claims he doesn't want "obnoxious things", such as "reproducing a huge disclaimer that is written in all caps".
The reason that all caps language is used is because of a history of court decisions and laws around what is required to effectively disclaim implied warranties. Right now, the license does not properly disclaim any implied warranties, which puts the developer at risk.
Worse than this, the text block he suggests putting in text if you want to disclaim warranty (http://www.wtfpl.net/faq/) would likely be ineffective in a lot of places.
I know everyone likes to think they won't get sued. But it does happen. It will wipe you out. It isn't worth taking a moral stand against a few lines of text in a source file.
To answer your other point, if you want good licenses, you have to actually know what the hell you are doing.
I really do understand that people want to not have to give a shit about this stuff, and have simple and clear licensing. Really. But this is not the path to accomplishing that.
The legal and political world takes a long time to adapt. Things like like free and open source software will eventually be sanely handled in the law. WTFPL is not going to be anywhere in that history.