In VoG anything above lv 30 is almost completely irrelevant. If you had the most kills that simply mean you were the best player, or if the team wiped several times, your team just sucked. But if you were the MVP of the bunch you likely would have managed the same with any other class (generally speaking). In fact I did manage the same in CE HM, half as Song of Flame Sunbro, half as Voidbro. Obviously the good players won't drag the team down, if all others are worse.
I'm not sure if I made it clear, and if not that's my bad, that my stance on Fireborn mostly, if not exclusively, applies to PvE. In PvP it's whole different story, and there the main problem is people not looking before they res and giving the others a free kill by resurrecting right into a shotty or Golden Gun. I prefer Voidwalker in PvP, and even then I somewhat suck at it, so I can't comment on Crucible much more.
used correctly and your a decent player
There we go. That's the reason for my opinion. Because I don't want to say the majority of all randoms I get matchmade with suck, but Actually that's exactly what I wana say. You seem be a competent player who knows what they're doing and likely would do well with any class. But enough others, well, aren't. Far too many people stick to Fireborn and never use their super, even when I created a literal 50+ Orbs (VoG, Obsidian Mind nuking during Confluxes/Legions; none of the 4(!) other Sunsingers used their super even once) for them to recharge 10 times over. And they won't play aggressively to actually use FB either by intentionally dying or at least taking risks, and when they do die and res, they totally waste their super and barely create any Orbs most of the time. Can you tell me how that is not dragging down the team by effectively denying them the Orbs and damage output (plus possibly Song of Flame) from using Radiance?
It's not that there's no ways to use Fireborn as a powerful tool, it's that the great majority of people don't know how, and instead use it as a crutch, dragging their team down.