I've been checking people both gear and other jobs recently when in dungeons.
Had a Holminster Switch party where the tank had Zurvante(i265), healer un-upgraded SB relic(i290) and DNC their starter weapon(i260). Rest of the gears were decent but their weapons were all missing 100+ ilvs.

However, looking at these people's jobs I could see they all had one or more jobs at lv80. So it wasn't first timers working through the MSQ, but instead people lv'ing alt-jobs who couldn't be bothered getting better weapons.