Most servers' communities have already worked out the rules that are generally followed on their server, even if not everyone is in total agreement about those rules.
That changes with the start of world visit when players will be doing hunts on other worlds that have a different set of rules compared to what they are used to. There is nothing that states they must obey the rules conventions adopted on the world they are visiting.
What will the end result be? We'll have to wait and see. I think YoshiP is overly optimistic if he thinks players on an entire data center will manage to come to an informal agreement about hunt etiquette in cross world hunts.
Except that's not obstruction of game play by another player. That's game design that generates rewards based on party participation and not individual player participation.
If someone doesn't want to have to join a party to receive the full reward, then they need to convince SE to change the reward structure for hunts. Unless SE makes that sort of change, the player is obstructing themselves by choosing not to join a party.
As for someone ending up solo because the wrong number of players showed up, there's no need for anyone to be solo if the community cooperates. We shuffle people between parties to do our best to make sure everyone who shows up gets into at least a Light Party, which is usually enough to get full credit as long as we don't have an exceptionally large group present. On those rare occasions it's not, partial reward is still better than none at all.
One thing we do when we have new players join our community - we tell them when a relay goes out you drop what you're doing and go straight there if you want to be part of the kill. Most people are willing to be patient for 3-5 minutes for others to teleport and travel. They're not going to wait 10 minutes because you wanted to do other things first.
If the mob is going to require specific player activity to spawn the mob, then SE should ensure those who specifically engage in that activity to spawn it get rewarded. It's a poor system that gives random players the reward instead of the player who put in the effort.