An entire group of 31s I was just with did the Hardmode up to the deathsinger. No 32. We are fine. Just 10 percent less damage than you 32s.
Edit: I get that 31s can't do the entire raid on their owns like a 32, I'm saying why decline one for not being 32. If they can't pull their own weight kick them. Some can some cant.
-
But this is why you join a clan so people can learn how well you can hold your own without questioning your level as "much". Crota on hard is a beach, one person dies its a chance of wipe if you can't kill the oversoul, boomers are much harder to kill and shoot like a machine gun howitzer and can make a Guardian drop like nothing. No chalice as well so you will need alternative means for healing (suros, red death, some armor, character abilities.) If you haven't ever tried it as a 31 you'll see why they wanted 32s when you do.