Instead of doing a key that u can only craft or buy 2 times a week for the very only late game activity, u should make umbral shards harder to get and get the key to do what any other key in the world do, open more then one time the same door.
lets say keys are free but u get less umbral shard from dungeons, great everyone would be doing it. (grindy, but acessible content)
in this case u would see your grouth by the amount of effort u put in.
now with 2 keys a week. (not acessible at all)
after u did your 2 keys you are left in a limbo with only a few options, OPR for fun (full of bug and pve, u can’t have fun in there) or leave the game and wait for the cooldawns.
in this case u have ppl questioning what should i do with my free time.