At least for ordinary retail investors it is.
For most people, owning stocks or ETFs is a zero sum game and for some it’s a losing game.
The stock markets goes up a couple of percent, then it goes down a couple of percent. Rinse and repeat.
The only winners are big banks and institutions that make money on transaction fees, leveraged products, ETFs and so on.
Beware everyone! Don’t come crawling back saying I didn’t warned you! Keep your money in cash only (or gold if you really want to) because then YOU are the master of your own money - and not scammers in the stock market.