I don't really get your reasoning, kokoloko. Snorlax has been used to check Raikou and Zapdos since Gen II, now it so happens to also be the best answer to Chandelure and you think that's bad because it restricts teambuilding? With that logic, DH Project players won't be able to succeed because Lax can't be used, right? I'm sorry, but that's how I understand your post, feel free to refute me later.
Chandelure is an incredible threat, mainly due to the fact that it gets some good switch-in opportunities on the most common Fighting-types which have to rely on Stone Edge to KO it, which in return can give free switch-in opportunities to another offensive mon such as Flygon. That by no means makes Chandelure overpowered, but I'll try to follow up a line of thought.
60/90/90 defenses aren't crappy when combined with its good set of resistances and the fact that its low Speed allows it to invest in HP more easily. That 145 Special Attack could mean that it's an incredible wallbreaker and makes stall unviable for the thought that very few slower mons can take two hits and KO back, right? That was the reasoning used by many on Queen's suspect discussion for RU, a tier which has banned many Pokemon over the years in order to balance stuff, but ultimately decided on keeping Queen. Now I know that the playerbase is different and I shouldn't make comparisons, but try to think this: Queen is a powerhouse with an effective base 112 Special Attack when using Sheer Force-boosted moves, has many resistances similarly to Chandy but is immune to Toxic, Thunder Wave, and Life Orb recoil on top of that, while also resisting SR. Chandelure is much less of a threat to defensive teams, because even with that impressive 427 Special Attack stat, it takes full damage from all entry hazards, is hurt by Toxic and Thunder Wave and takes LO recoil, though it can use Pain Split to minimize that. So the biggest thing it has against defensive teams really is Trick and that massive firepower—which is still not enough in many situations—, because unlike Nidoqueen/Nidoking, it doesn't have to be attacked directly to be disposed of.
Now that that's out of the way, we should then look how Chandelure fares against Offense, since Stall can beat it without having to attack it—whether Stall is viable to begin with is another discussion. Now, it's true that very few offensive mons can switch into its Specs boosted moves, Flygon for example only has a 1 in 16 chance to survive a Shadow Ball after SR and KO back with Earthquake. Therefore many offensively-minded players will turn to CB Lax as their answer to Lure. Is that really that bad? Very few stuff can take two neutral STAB Returns to being with, and Snorlax makes a great offensive check to a myriad of other threats, particularly Raikou and Zapdos, so I'm betting Snorlax would still be useful on offensive teams outside of the premise 'Because fuck Chandelure'. However, it's true that outside of CB Lax and maybe Houndoom—which has the problem of being rather predictable, I really pity it because it would be one of the better Pursuit trappers due to that WoW immunity :\—very few things can switch into its STAB moves, however Flygon switches into Fire Blast without dying 90% of the time barring crits, Heracross has an impressive 43.75% chance of surviving a Specs Shadow Ball after SR—that's a neutral hit coming off an effective 640 Special Attack—, and many things can revenge kill Chandelure, with the added benefit of some being able to Pursuit trap it. I used Specs in my example here because it's the hardest thing to switch into, Scarf is more easily dealt with by Offensive teams due to the fact that base 80 Speed doesn't cut it against Offense, while SubSplit is really nice, but I can't see it working when it's hard as is to switch into Offensive teams, outside of Choice-locked moves or after a kill—not the best scenario. Now I'm painting this just because it'd seem as if Snorlax is the only thing able to switch into it, it's the only thing that can come in against Specs nearly risk-free, but not the only check to it, which was the reason many used to not give Chandelure S rank. Moreover, there was the thought that, once it had gotten a kill, it could be fodder for something else to set up and win a match.
Notice how, in my entire post, I didn't mention Porygon2. Why? Because the best thing it has against Chandy is entirely dependant on the Chandy user, and leaving your ability to counter a Pokemon in the hands of the other player is not something I enjoy. Moreover, Defensive Duck hates losing its Eviolite, so FF version can still beat Porygon2 with Trick+HP Fighting:
252+ SpA Chandelure Hidden Power Fighting vs. 252 HP / 80+ SpD Porygon2: 158-188 (42.24 - 50.26%) -- 91.8% chance to 2HKO after Stealth Rock
Not exactly what I'd call a 'counter'.
All in all, Chandelure is indeed suspect-worthy so I have no issues with that, but I'd never think it's flat-out broken, not even that restraining since Snorlax is just THAT good for any kind of team. I might change my mind if I find that not using Snorlax makes me completely weak to it—especially when it's wallbreaking for Raikou—, but I somehow doubt it. If anything, the biggest problem with it is that while it's alive, I have to think twice before using Heracross's STAB moves, or locking Snorlax into Return, but that's the same problem with many other Pokemon, so that will never be enough of a reason for banning something.
EDIT: below, I never meant to say that not attacking Chandelure is good, but I meant that unlike Nidoking/Queen it can be worn down by switching in and out. Also, relying on Specs HP Fighting isn't precisely good, I'd say Trick+HP Fighting is better since you're not locking yourself into a weakling move (and why in heaven's name would you lock yourself into HP Fighting against Umbreon? o.O That's quite a faux pas imo). Either way, that point is moot since I doubt pure Stall can do much in this metagame, but yea, Chandelure could be worn down more easily than other stuff. No one's arguing about Kaleidoscope being great to prevent SR from ever being up—although if it can't prevent it, it'll suffer a lot since it has 3 SR weaks—, or how Blastoise could spin even easier against Stall teams. What I was trying to say was that it was easier to deal with that other stuff for Stall, since pretty much the only thing it had on its favor was Trick plus its amazing Special Attack. Sorry if I didn't make myself clear.
And again, I doubt Chandelure forces you to use Snorlax. As I said before, then DH project would have to be revised or kept on hold until they decided to ban Chandy since it would otherwise win every single match without Snorlax on the way, right? Btw, neither Rhyperior nor Queen are that reliable since they fear HP Grass or HP Flying/HP Ice/Extrasensory— otherwise they're pretty cool—, and I'm pretty sure SubCM Raikou can beat non-Analytic Porygon2.
In the end, I was just trying to look into kokoloko's reasoning to say it was flat-out broken. I won't argue that banning it would make the metagame more diverse because I'm trying to talk about facts here, not assumptions just for the sake of having a good argument, so I can't really say if a meta without Chandy would be better or worse. It would probably be better, but is it worth banning it just because of that? And then, is it the biggest thing that's preventing us from reaching a balanced, 'fun' meta?