This was my experience trying out "traditional betting" for the first time with Betfair last Worldcup, and some other platform I tried out before as well. Not sure what Kalshi/others are doing that is so different?

If you're going to gamble, it's probably for the best that your counterparty doesn't also control the platform. I'm not saying that justifies being able to gamble frictionlessly, but it is marginally less exploitative. Eg, back in the day bucket shops (which sold binary options, like prediction markets do) would increase the spread in proportion to their assessment of your skill such that you would lose even if you were more skilled. In a proper market the platform makes the same amount of money whoever wins.

So, not all that different, but marginally less exploitative. I've never looked at Polymarket but Kalshi and PredictIt slid steadily from things of at least plausible real economic value (a market where it was conceivable [if unlikely] someone would be hedging their insurance contract or something) into total nonsense with no non-gambling function like whether someone would tweet a certain word.

I think prediction markets could serve a similar to a futures markets and have a functional purpose in the economy. It could be useful to generate real time estimates of the probability of some events that no one can control and have real economic consequences, like a hurricane. But evidently that's not where the money is.