The game uses lookup tables. Some outcomes are prioritized over others. Blizzard’s brilliant plan is to prioritize undesirable outcomes over desirable ones. This is a fact. It’s been well established that almost nothing in this game is completely random. They did this so they can have loot explosions without people getting perfect gear in an hour. It’s the same reason there are useless legendaries. It’s the same reason all forms of RNG outcome mitigation, like Kadala, have a higher chance of giving you the item you want but require a similar expenditure of time farming materials as simply farming random drops as efficiently as possible. Confirmation bias goes both ways. Some people remember when they win the loot lottery some remember when they lose. What doesn’t change is that you will lose far more often than you win. That’s why the game isn’t Progress Quest nor should it be. People can argue about the time spent versus reward ratio but Blizzard is using their own metrics for that.
I highly recommend people look up and play Progress Quest because it’s quite instructive about the type of game so many people ask for but don’t really want to play.