What's happening is I've seen a lot of people level up a lock alt and "think" (my opinion) they should be granted fire and if it's not achievable with low gear, the boss should get nerfed. I've known a few guildies with this QQ -____-. I can't remember the exact post from blizz within the past 1-2 weeks that stated they weren't gonna nerf it soon due to the fact it was suppose to be cosmetic reward for those who managed to complete.
With obtaining ToT LFR gear and practicing the mechanics, it will make the fight a lot easier to do but don't expect to just ROFLSTOMP with 500ilvl. You have to utilize your warlock skill arsenal. It's not about "omg blizz, wtf I did 300k burst but died to his Chaos Bolt.... NERF IT BLIZZ." There has been videos of people achieving it with 470 and there was one with someone in the 460s.
Grats to those who have gotten their fire though, and those that haven't, keep at it. You will get it eventually.