That happened during the original design of the game. M:tG was one of the first products to sell you a pig in a poke. That was the concept!
I've seen people say that it would be nice to regulate loot boxes in video games, but they can't figure out how to do it without banning Magic's business model. I never understood why that would be a problem.
The genius thing about Magic is that it doesn't place individual value on a card. Even if there is indeed a "drop rate". But that drop rate doesn't always evaluate to higher value. It correlates and they try to make if so, but that's ultimately a different marketplace who externally decides what has value.
Video games don't have such safeguards. It's all on the studios servers and they can adjust value on the fly. Unless lootboxes are all cosmetics there's a more direct hand in the market that can influence value and worth. And it all comes crashing down the moment the studios decides to shut down the servers. I feel that's an intrinsic difference that places a video game closer to a casino ("the house always wins") than a TCG (throw out what you think is worth and let the community sort it out).
Not sure if they were always this forthcoming about the 'slotting', but I do appreciate it.