Percent who say they "frequently" or "sometimes" engage in:

online sports betting: 23%

prediction markets: 14%

Not a huge difference. I would say the two things are not materially different in popularity (in this one survey).

The article (which I agree is a bit crappy) even goes out of its way to mention the two things separately in the sentence "For someone to win in a prediction market or sports bet, someone else has to lose." They are different things, but they are both zero-sum, which is the point of the article. So the two things are not really different in principle, either.

I can't really grasp what your point is or how you can criticize the article for not being unsupported by the link, and then misrepresent the contents of the link.