It is not, played over time, a losing game. Just look at the lifetime graph of any major index.

If you just buy and hold, and don't panic sell during a recession, you'll win.

Will other more sophisticated players make money exploiting short-term swings? Sure. Will other players beat your returns? Also yes.

But that money isn't coming out of your pocket, so why does it matter? You're still beating leaving your money in a savings account, where inflation is outpacing interest.