Why is the next new job a melee DPS?

[Seraphor]

This ! I've been waiting for someone to tell that !
It was sure we will getting a melee because the standard composition of a full party is supposed to be: 2 Tanks/2 Healers/2 Melees/1 Physical ranged/1 Magical Ranged.

While is is the most common party composition, it's not one that the devs regularly promote. Some fights are tailored around it, but many aren't.
Their official stance is that it's usually 2T/2H, 1 Melee, 1 Ranged, 1 Caster, 1 Wildcard.
The 2 melee typically comes up due to melee generally dealing more damage, but 2 casters is also viable.