Why is Birb weaker than Bahamut again??

Baha Ruin III = 440 -> 500
Phoe Ruin III = 540 -> 580

There used to be 600 potency difference within 6 GCDs to counterbalance the extra 500 potency from Deathflare in Bahamut phase but now there is only 480 difference??

They patched this because the LV80 skill was weaker than the LV70 skill during Endwalker but they rolled it back??