I think Pyros does not require party content, and people just wander / slack / spawn until NM pop, group, down it, degroup, repeat. But the area is designed for that. Being low level, you can easily reach all NM except maybe Glaukosomething and Pentesilea (although people will raise on the way for this one). All other NM are close to aetherites, and they don't request high level to let you attune. Also NM give LOTS of XP compared to Pagos, so you feel like you "have" to do them to level up.
Whereas Pagos is putting clear obstacles to that progression we had in Anemos and now in Pyros by the map itself and the poor XP gain per NM. A few days ago, I assisted to a really heated argument in Pagos about (not) waiting walkers for upper Pagos NM. Higher level people were angry to wait for low levels because they do no damage to NMs and slow the fate grinding for each NM. I think players want to impose some kind of unique pattern on all eureka zones though they were not developed with the same ideas in mind, and it is obvious in Pagos.
IMO Pyros feels a bit more individual (as logos system basically allows you to do a lot on your own), but I never actually got any problems to join or form a group and do NMs or spawning for high level fates. And I also met funny and nice people as I did in Anemos and Pagos, which is what I like the most in Eureka, compared to FFXIV in general.