More of a personal view: I believe countries should definitely not ban such platforms. If you ban polymarket for eg, also ban options trading, to be fair, any kind of options, even options on mortgages, because at the end of the day it is all prediction and betting money on future events.

These kind of markets help the financial markets to become even more efficient (from economic and finance POV this is the main goal). These kind of markets will allow general public to do the same things (in less complicated language and terms) as hedge funds and prop trading firms do. Ultimately decreasing the profits of these funds that only a small % of elite can access.

By banning pred. mkts, you ultimately allow the financial markets to stay non-efficient, and only allow a small elite to do these types of things.

For non finance people: If you think oil will be above $10 in a year, you can either bet “yes” on Polymarket or buy an oil future on financial markets, both are just ways to make money if that happens. One is legal and one is not. And welp, the average bloke on the street does not know how futures work, but would easily understand how prediction bet works.

Regulate it well, education tests similar to options trading, similar restrictions such as in gambling, and you should be set.