Question, why does Bard and Machinist share the same core mechanic?

[Altena]

Rice, I won't write a long winded response because honestly I can't be bothered..

I can't agree with you, but that's totally fine. I also don't have extensive experience on playing MCH at end game.
I also can't agree that turret position is completely irrelevant, especially on the later fights (such as A7S & A8S). Both arenas are quite large, and both fights involve quite a bit of movement.
Our MCH actually requested not to handle the physical DPS jail in A7S due to having to resummon his turret. However like I said earlier, my knowledge on EG MCH is 2nd hand information.

Another comment from the MCH was that they hate BRD as it feels clunky and horrible to play compared to MCH.. To me, that opinion shares the idea that their overall playstyle is considerably different (as was my opinion without this input).

At least to a point - as like I stated earlier, my opinion is of that most jobs filling the same roles have similar backbones.

Also your comparison of PLD and DRK makes me both laugh and cry.. Especially considering you are arguing that BRD and MCH are too similar.. Sorry but I definitely can't agree with you on this. DRK and PLD are even more similar than BRD and MCH if you wish to argue that point. Dark Arts is barely even a mechanic. "Pop this buff to chew mana to make these 3-4 skills stronger, but generally you won't use these 3-4 skills without DA anyway"... I mean what do you even use DA on, aside from C&S, DM and SE? Could argue Power Slash is ok as well (hence the "3-4"), but that's honestly about it..

It's more of an annoyance than anything else. They might as well have tacked the MP cost onto the skills and done away with it, as it adds very little to the class in terms of gameplay..