alt Hacker NewsIsn't Polymarket very low stakes? For example "Will Trump acquire Greenland before 2027" market (the main one for this issue) has only 14m USD volume. This is like 2 orders of magnitude less money than is bet on El Classico 2 times a year.
There are risks connected when prediction markets run wild but Polymarket ain't it. There is also utility. It has high predictive value (it beats polls for elections from a little sample I've looked at) and allows you to make better decisions.
It beats polls for elections ONLY until someone notices it is being used as the basis of news stories and figures out it will be four orders of magnitude cheaper to manipulate that small market and make the news idiots broadcast that opinions have changed than to actually deploy all the adverts needed to change the opinions.
The very low stakes you point out make this even easier to put a thumb on the scales.
Goodhart's law: "When a measure becomes a target, it ceases to be a good measure"
The point of the article is that as soon as the "news" started reporting on prediction markets or corporatized gambling as if it was a measure of sentiment, it ceased to become a good measurement. That point has long passed.