It's controversial because people get into arguments about it. He included it in the list because it's also trivial and silly, as a way of saying that Wikipedians get into arguments about trivial and silly things ( http://en.wikipedia.org/wiki/WP:LAME ). It's a joke of sorts.

Trivial indeed:

  Are U2 an "Irish band" or simply a band that happen to be
  from Ireland, since two of their members were born in the
  UK

Some people say the site lost its way when each kind of Pokemon didn't have its own Wikipedia page.

There's Keldeo, Meloetta, and Genesect - the missing Pokemon. They are only present on a Nintendo game, and only if you hack it. But they are vaporized, 1984-style, from the English Wikipedia; as they don't exist in the real Pokemon world.

At least, that's what I can glean from 5 minutes on the discussion page here: http://en.wikipedia.org/wiki/Talk:List_of_Pok%C3%A9mon_(599%....

If I were interested in Pokemon, I would assume that would be an interesting piece of information.

Yet one editor has kept it surprised, and apparently fights like a wolverine if anyone tries to push an edit past him. And this is a fun article.