I’m not trying to demonise anything
if enough people end up blocking them, they will find it hard to even find a 12 man UQ.
Again, demonizing them. Almost counts as griefing if you think about it.
if someone really doesn’t want to play with other people, then why are they playing an online game in the first place, and joining UQs in the first place that are designed around multiple parties working together?
Maybe they are stressed out after a long day. Maybe they are someone (based on current UQs) that got disconnected from their actual party for Deus and are doing the run to rejoin the group for the rematch? Maybe they got tired of all the party issues that have arisen with random strangers, such as kicking people at the end loot before they get anything. Honestly, I probably wouldn't party with you either. I either lead my own party or stay in control of how I leave the quest.