Diablo Immortal has been given an extremely rough time for this model of business which is perhaps not in the way it should in light of the fact that free-to-play games like Genshin Impact and Lost Ark have a lot of gacha-based mechanics that attract big-spending "whale" players. Diablo's popularity and fame with a large PC gaming community Diablo IV Boosting, accumulated over the course of a quarter century, is definitely one of the reasons. However, it's also true that this particular system is problematic, and the very character of Diablo games has something to do.
If you purchase legendary crests, you are not buying a single roll of dice like the case with a FIFA Ultimate Team card pack such as. You are purchasing a chance to play with the dice, to get into the game engine and tweak the drop rates (slightly) in your favor. These addictive gaming mechanics aren't isolated from the addictive gameplay mechanics. Instead, they are linked directly into combat and loot drops inside the game. Diablo is uniquely well-positioned to achieve this. As my colleague Maddy Myers pointed out, these games heavily focused on loot always had a slot-machine feel which Diablo Immortal's model of business makes the game appear as if it were.
Blizzard has been at pains to highlight that the monetization of Immortal can be ignored until the final game and it's true and claims that the vast majority gamers enjoy the game without spending even a cent, which is feasible. However, it's not true that the greatest enjoyment in Diablo games lies in playing through the story rather than maxing out your character. It's just as untrue to say that the games have always been engineered to engender an obsession with hitting the power level of their players. If you have a predisposition towards addiction to gambling, toward the addictive qualities of Diablo's Item gameor, more importantly and both of them -buy Diablo 4 Boosting- the crest system of old is exploitative and potentially very damaging.