<canadian-pedantic>A kayak is longer and thinner and lower to the water and is often covered. A kayak is typically paddled using a double ended paddle. In Canada, the boat in the article is a kayak; I don't think anyone here would call that a canoe. A canoe is deeper, wider and fatter (like some Canadians perhaps ;). A canoe can transport a lot of cargo but is also light enough to carry across portages. Many years ago native people and fur traders could travel entirely across Canada in a canoe. Some people still attempt this feat.
In other parts of the world the boat in the article might be considered a canoe, but I would say not in Canada.
</canadian-pedantic>
"A canoe is deeper, wider and fatter (like some Canadians perhaps ;)"
Not sure about Finland (where the article's author lives), but a wide, fat open canoe is actually called "a Canadian" in many parts of northern Europe.
The concept of an "open kayak" sounds pretty confused, though, given how they were originally built (skins wrapped around a thin wooden frame) and used (coastal sea regions, including the open sea).
In other parts of the world the boat in the article might be considered a canoe, but I would say not in Canada. </canadian-pedantic>