Games with DRM crapware like Denuvo and many multiplayer games are more difficult to pirate, but the basic Steam DRM is pretty useless. That's good, in a way, because when Valve inevitably goes bust these games will still be playable.
However, if you can afford to spend 15 bucks on a game, I don't see why you'd go through the effort of downloading (and virus scanning!) games. For kids and poor people I can understand spending the extra time and effort, but for people with jobs that value their free time I don't see the advantage of just paying for the game.
I suppose the lack of demos is a reason, you don't want to spend 15 bucks on a game that turns out to be boring or broken. I pirated CP2077 to check if it could run on my PC but after a few hours I paid full launch price for it, they could've convinced me with just a demo despite the negative media attention. I still remember the Just Cause 2 demo where the demo alone was a great game you could play for many hours and the full game was even better.