LAC The main reason for this is the very high exp rate, which gets you to 4th job without the need to play 3rd job for more than 30 minutes.
If that's the main reason, then adjust your xp rate on the NPC and enjoy the lower rates experience.
Indeed sometimes sucks to use just one build to do a lot of damage *cof farm endgame gears cof*, but there is variety of builds for 4th jobs. I'll give an example for AC: Crown of Good and Evil combo (melee focused), Dimensions combo (ranged focused), Furious combo (can be magic and melee focused).
No one is pointing a gun to anyone to use the meta builds, they're just meta/optimal for majority of content. If you enjoy using an alternative play style, cool for you (I am really impressed with your gifs, never expected to see those)! But in the other hand, you made it possible with some MVP cards wich means that they're possible but with a enormous investment to make it work. To me, getting those are the endgame, so I have a loooong path to get in this "off meta" phase.
Obviously we can experiment without the MVPs, and there I se why you want new gears to make the off meta build viable. But as a lot of people have mentioned, the equips can just break all we have in control - yes, every class being busted and super overpowered would be fun but then we go to the path of "oh just use your X skill build equips, press F1 and kill the boss". Also, if gravity decide to nerf/balance classes/skills that now are the top tier DPSs, people will migrate their builds to a better one. No one wants to be weak in a game where is mainly PVM and the monster get A LOT of damage reduction on later content.
TL;DR: Leveling too fast? Adjust your exp rate. Off meta builds are off meta exactly because of the lack of equipments that support them. Blame Gravity, but don't break the game.
