As the person who said the title quote, (Although I was agreeing with someone else when I said it) I feel I should respond.
So many people, so many times have articulated this better than I will now. If you'd like more explanations, I would suggest searching the replies of some of the top rated ghost ratings for "WTA" or "PPSC". In particular, I recommend the writings of Babak, although he does tend to be a bit extreme, claiming that (As it was then then) phpDip was ruining the diplomacy community by offering PPSC.
But whether or not PPSC is ruining diplomacy, (I personally learned to play diplomacy on this site and started playing PPSC before I even knew anything about the argument, and am now a convert.) he's right. It IS a disgustingly horrid variant. This is primarily because it incentivizes playing to lose. There is almost no incentive to stab an ally that is going for a solo, but rather to continue beating up on smaller powers in order to gain as many SC's and points as possible before the game ends. As a result, the solo rate (Which should be regarded as a measurement of poor play, more later) is far higher in PPSC. (Although it is still abnormally high in WTA than it is in other places, like play by e-mail. For more on that, you should see this thread: http://www.webdiplomacy.net/forum.php?
threadID=662653) In a WTA game, people almost always gets stabbed around 9-10 SC's, as should happen, so that they don't solo. WTA isn't so much about winning yourself (Although that certainly is the goal, it is far more difficult) as it is stopping others from winning.
Some people complain that WTA promotes draws. This has always baffled me, as a true 7-way draw, where no player can make no progress is the outcome of a perfectly played game of diplomacy. (I've only been in one, sadly.) A high solo rate is indicative of poor play. In quality play, the remaining players would put aside their differences and unite to stop the solo, and indeed one only solos when this does not happen. For more on draws, "strong seconds" and solos, I recommend this article, by the creator of diplomacy, Allan Calhamer: http://www.diplom.org/~diparch/resources/calhamer/objectives.htm
All of this being said, it's unfortunate but true that I think PPSC has some advantages. First, it encourages people to not CD, which was a HUGE problem when this site began, and one of the instigations for the point system to begin with. And to be fair, it accomplished its objective.
Some claim that it's fair to give more credit to a player who survives with 14 SC's than one who survives with two. This is a misunderstanding of one of the fundamental assumptions built into the creation of the game, namely that any 18 SC army can conquer the rest of Europe with ease. Ergo the game is "called" for the player at 18 SC's, as to not waste time. This is discussed extensively in Allan's article from above. Ergo, even if you have 16 SC's at the "end" of the game, it is presumed that you would be wiped out (And you almost always would be) and would eventually have nothing. If we accept this assumption, which, as Allan points out, is almost always true, then WTA is the only logical scoring system. Because a survive is really a loss, "a draw, then, is the reward for survival in a dangerous world." People should stop conceptualizing a "survive" as different from a loss, and start conceptualizing draws as survives.