Apparently Fire has scaling issues, but Why ?

[Doty]

Hi guys, I have a question regarding the apparent scaling iusse fire has.
There are a lot of people who claim, that fire will have problems in TOS when you get higher and better gear.
And I wanna know why ?
Fire has some pretty decent logs at the moment. I know its just heroic and we should not take it too seriously, but
objectively... You know what i mean.

Fire has issues with high haste, I know that, but Nighthold is gone. Whispers and metronome are gone.
The 2(t19) set that devaluates crit is gone.

So why does fire still have scaling issues ? Just a myth? And why does GS(Frost) scales so much better ?