Why not make SMN's Bahamut do Megaflare when it's summoned

[Payadopa]

The reason is simple, just because with the current summoner's mechanics, it wouldn't work.
If Bahamut deals more damage than Phoenix, as it was the case in 6.0, a level 70 summoner would be stronger than a level 80 summoner,
because summoning Phoenix would be a reduction in burst damage.

And people wonder why the game is so stale job-wise. Just another prime example. I mean Phoenix was lower in damage because it could also heal. Makes a lot of sense to me. But then min-maxers threw a hissy fit and the potency got changed. Small change but exemplary.