I personally think that some (if not most) of the descriptions of the types are kinda off. But I guess that it's okay since it's one of those humour articles. But I still feel the need to state my opinions on this.
Dark types would fit better as the quiet loner; has emotions (probably very strong ones) but doesn't wan't to show them to just anyone, focused in ways others are not, sometimes puts on a serious mask around new people (or people they know that embarass them). Ultimately they are loyal comapnions but only get close to a few people, and probably spend a lot of time thinking instead of talking (making them ideal introverts). They have a great sense of pride, one of a couple traits shared with fire types. One thing I can say is if you can get them to want to do something, you will never find one more determined, save for Fire types. The best example I can give is some of those Final Fantasy Heroes; Leon Squall, Cloud Strife, Lightning Farron, Cecil and/or Kain.
Fire Types aren't so much as directionless, arrogant or rebellious. They are just the raw manifestation of determination. Highly emotional and open, it's like what happens when a Dark type becomes extroverted. They follow their greatest goal with reckless abandon, along with any other goals they come across that seem worthy. The shear blaze of their determination means that it's near impossible to defeat them, as they'll just keep getting back up. They have a sense of pride that rivals most others. Best examples include a bunch of characters from the various digimon seasons (The ones with the fire wielding lizards), Naruto, And a whole bunch of others. Seriously, much like there's a fire type starter each generation, there's a fire type personality as the hero in almost every Anime.
Ice types; That's a hard one to explain. They carry themselves with utmost calm and grace, and often have an inteligent mind. However, it is very easy to miss them as they have less energy than many other types. They show fragments of emotion at a time, never being over-taken by them, so one may have to pay closer attention to emotional cues than most other types as the most they may give for happy is a slight smile and a tone of amusement in the voice. One can also expect ice types to take a lessurely pace, and you don't often see them stressing out. There don't tend to be many notable examples, and the two notable ones I know of are bad examples (as in 'taken up to eleven'); Edward and Bella off Twilight.
Those are the main ones I wanted to give my take on I may Give more if I feel compeled.