Key depletion is not a punishment. Acting like it is is ridiculous. If I make a crap group which falls apart and my key goes down by one level, all it means is it’ll be much easier to two chest on the next round and still be a beneficial outcome to me.
Further if you failed a key because you made a bad group or because you could not perform, then you should be put back down to where you were because maybe you’re not at that key level yet. And sometimes you just get unlucky. So what, 2 chest the key that went down a level.