I've said my piece on the problems of Overwatch's loot box system – that you can't purchase individual skins with real money, and you don't have any reliable way of earning in-game currency, so getting cosmetics is funneled entirely through loot boxes, which guarantees Blizzard makes more money than you would otherwise want to spend in exchange for very little effort – but I have to stand here and thank Heroes of the Storm for reminding me that it could still be much worse.
With Heroes of the Storm's "Progression 2.0," Blizzard has introduced into their MOBA a loot box system that makes the one in Overwatch seem like a harmless Dr. Jekyl to Heroes' Mr. Hyde.
I want to be clear, though, that how this works in Heroes of the Storm is perfectly acceptable because you still have the option to purchase these skins individually with real money. It is not forcing you to go through loot boxes the way Overwatch does. My concern is that the Overwatch team at Blizzard will look at this Heroes of the Storm update and say "hey, that's a good idea."
The primary difference between loot boxes in Heroes of the Storm and those in Overwatch is that you can purchase higher-tier loot boxes in Heroes of the Storm that guarantee cosmetics of higher rarity. So a "rare" loot box will guarantee at least one rare item, an "epic" loot box will guarantee at least one epic item, and so forth. Again, this is fine in Heroes because there are other ways to get the cosmetics involved, but, in Overwatch this would only make it more difficult for people to get the skins they want, thus encouraging more and more loot box purchases, all the while the Overwatch team has no incentive to keep making new and more desirable skins as they're already making enough money hawking the mediocre ones they already have.
As anyone who has read my stuff on GR and other websites can attest, I was raised as a gamer in the fires of Dota 2. Despite being clean of Valve's great MOBA for almost three years, I've still spent more time in Dota 2 than the rest of my Steam Library combined. So, naturally, I see things that other games do through the lens of Dota 2, what is easily the most consumer-friendly free-to-play model that ever has been and likely ever will be on the market.
Valve was and is a total bro when it comes to these cosmetics. They gave you one each time you leveled up, allowed you to purchase them directly with real money, meaning that, if you wanted one skin, you only needed to make one purchase to get it, and you'd be free to never buy a single thing ever again. They also allowed you to share these in-game cosmetics among other people in the game. So, if you had a sweet announcer pack or a HUD skin, you could share it with other people playing in the same match as you, so they could also use it for the duration of that game.
If Overwatch follows in the footsteps of Heroes of the Storm, implementing higher-tier loot boxes for more money and continues to not allow individual real-money skin purchases, this is bad bad news for the Overwatch player. Overwatch loot boxes are already bad enough.