I think people are kinda getting ahead of themselves here. Yoshi said mobs will be tougher to solo and you'll need to use all your skills if you want to take on more than one mob at a time. The mention of looking for help in beastman lairs was not because they are group content but because the mob density there will make it hard to fight only single mobs at a time. You won't need a group. You could solo it if playing cautiously or duo it fairly safely. Enough people have complained about a lack of challenging solo content that they clearly see a need for this.

They NEVER said anything about open world group content.