I would say that fragments for at least basic essences and skills actually drop at a pretty frequent rate - if you're specifically after those items and doing what it takes to get them. There are routes for awakening fragments an 8 person group can use to get hundreds in a lockout. Anything that can be farmed with reflect is naturally going to be simple to get once a player owns exactly 1 lost reflect, with added efficiency for a levelled tank class and 1 essence of the irregular. Clusters themselves are also efficient and valuable as a group farm target.
The thing is, I think players firstly don't approach bozja as something where it's valuable to fight non-skirmish enemies, probably out of habit for the eureka NM train. And secondarily, players seem to approach item farming from the perspective of different MMOs that split drops, and incentivize not grouping to encourage viewing anyone farming the same item as you as competition. In this game, the larger your group is the better - you can get items from the other side of the map just because your group has credit, even if it's not a mob you personally touched - and this doesn't affect your other party member's drop rates. So generally speaking if you make the largest group possible and just fight everything, you'll be basically swimming in fragments. But it's like there's a block people can't get over to actually group up and do that - like people's prior MMO experience makes them think it shouldn't work which prevents them from doing it when it does work, or something.
Or people are trying to rank up and all that and "farm everything non-skirmish" is naturally not gonna give mettle, so there's that as a consideration.
