The Masked Carnivale can be done solo, spells can be learned solo, you can solo dungeons with Basic Instinct and the level 30 totems. It can 1-shot many things, such as FATEs, using spells such as Tail Screw or Ram's Voice + Ultravibration.

But it does have party-related endgame content, yes. They went in the direction of creating lore that entire adventurer squadrons could enter dungeons as blue mages and fulfill the typical roles of tank, healer and dps using blue mage spells.

You can PUG some of the raids involved for the Morbol but realistically this is more likely to be the easiest ones, T5 and A4S. The others can take multiple days, weeks or months of progression.