None of those reward anything meaningful in the context of player power and they are never offered in a way that preempts content. IE, you can buy 1-100 skip to "catch up" but that's it, you cannot bypass current content or directly purchase loot or loot rolls. It undermines the implicit market agreement Blizzard has with the player base that you must "earn" relevant gear.
I am not against the concept of purchases for items, it is a value proposition. In an FPS they may offer a DLC with new guns and you can only use them if you pay $15. First off, it's not random, everyone is aware of where those items come from. Secondly, the value is not diluted by layers of RNG systems.
Similarly, if you want to offer pure RNG loot crates on cosmetics, then the value may be unsupported, but there is no functional value to those items so who cares as they in no way materially affect the gameplay.