No, a stock is a share of ownership in a company.

Now yes, people bet on the derivative value of those ownership shares... but that also happens to basically every asset. If a stock is a prediction market, then so is corn, and gold, and your home.

The difference in my mind is that prediction markets and gambling are betting on outcomes, not long term behaviors. You could make the argument that they are the same, in the sense that buying a stock is "betting" on a company to do well, but I think you'd be making a silly argument. Stocks are intangible these days, but they were traditionally a physical thing that one would trade. If you're betting on prediction markets, there's nothing to trade after the event happens, just payouts.

Stocks aren't prediction markets, but options and futures are.

I think the stocks don't have a arbiter managing a discrete outcome between parties that don't have any KYC compliance.

Couldn’t we say that any market rewards prediction? And that this is generally seen as a beneficial quality that results in more accurate valuations with better liquidity?

Stock prices are a prediction built on crowdsourced information.

A commenter noted that MN already bans sports-betting, which is far closer to what prediction markets are than asset trading.

A closer stock analogy would be options.