True! I think as long as the item pool for those crates doesn't remove those weapons, they're good to use. I think if Snow Queen was removed for example it's pretty unlikely you would ever find a 100 hit Frozen Shooter in-game from a drop.
I think the other non-returning event gear (like anniversary blades + wings) shouldn't be used as it's not possible to obtain. But I also see that the TA scene is pretty small here... I think previous runs shouldn't be scrubbed because of this, but I think new runs should just use non-event gear. (Unless Eternal Night + Blue Phantom Field get their stats upgraded to match to 3rd aniv blades + wings! That would be my solution haha)
Great run @Tohru!! The idea of reduced demons and J/Z on this quest is a nightmare haha. Awesome