What if every job was like how it started?

[SnowVix]

Vague title so I'll elaborate: What if every job we have in the game was suddenly the same as how it was first introduced to 14? How different would the game be? This will not include cross-class stuff being accessible.
Got curious as I am crafting something behind the scenes to post about later and got this question

if every job were how it was originally introduced but without cross-class, it'd be unplayable. Provoke was Gladiator/Paladin exclusive. Swiftcast was Thaumaturge/Black Mage exclusive. Shroud of Saints was Conjurer/White Mage exclusive.

ARR/Heavensward jobs simply do not work without the cross-class system.