Slots are purely luck based, dice is purely luck based, plinko is lucked based we can continue to talk about what we can and at the end of the day we are not going to suddenly have games where being smart could mean you could make a profit, there is no way for that and it is mathematically impossible for you to win in the long term. So basically, all games are luck based and slot is not an exception to it.
The thing about slots is that you have a million of them and some of them are gamble a lot and win once to profit big, and some of them gamble some and make almost all back each time losing slowly, like there are all kinds of different slots.
That is how slots kind of work, I mean it is also all other games as well, depending on your odds there are times when you win right away, and there are times when you end up losing too much money without ever earning anything at all.
So long story short, we are talking about something not that big of a deal, we are talking about just gambling and it has always been like this forever since gambling was invented. Moreover some people love to gamble that way, some people gamble more dice and 50% and martingale or whatever, some like sportsbooks and gamble on matches, some like poker and beat other gamblers.
There are a lot of different ways you can gamble if you want to, and this is just another way you can gamble if you want taking a bit of risk and a lot of luck.