The past raids also didn't vary in light level on drops, so basing everything off the past isn't correct. Best case scenario I see is guaranteed drops and let the light level be the rng aspect. If you have a 311 ghost and a lower one drops, it's like not getting progression loot, but you can still use it. Bungie is built on layer after layer of flood gates to elongate the gear collection process. It's a great strategy, as you only NEED the raid gear to do the raid, so raiders are stuck collecting it, while giving non raiders plenty of aesthetic options to choose from instead. Raid gear is like pot brownies, once you try some, you get high and get the munchies. Then you eat another brownie and the cycle perpetuates until you've eaten the whole pan and can't get off the couch lol.