Chinese law will force game makers to reveal loot box drop rates
pcgamer.com
pcgamer.com
It's not perfect, but it's an 80/20 thing that would give a clear exemption to a lot of innocent loot scenarios while still covering most of the problematic/scummy ones.
Example: If it costs $0.99 to open a box, and the desired item drops from 4% of boxes, then it will cost you $9.90 for a 33% chance of getting it. But if the drop rate is 0.5%, $9.90 only gives you a 5% chance of getting the item. At some point you might just decide to buy the item on the secondary market (and indeed, these odds will influence secondary market prices).
(I personally think that these loot crates are effectively gambling. Even if the developers claim the items have no monetary value - because they have to, otherwise they're clearly offering you odds of a return on investment - the same developers often operate secondary markets which assume the items have a value, e.g. Valve and its Steam trading service.)