I'll be voting
no ban on moltres. My thoughts on Pangoro can be found in
this post.
Point 1:
Its speed stat is too low to sweep.
Its speed stat is not bad, for sure. Outrunning Hitmonlee, Rotom-C, Shiftry, Glalie (pre mega), and I suppose non-scarf Magneton and Exploud is neat. Moltres owns those pokemon. Slow pokemon who run offensive ev spreads tend to get wrecked by faster offensive pokemon. They also all (with a small number of exceptions) get owned by Durant, Houndoom, Mega Glalie, Delphox, Cobalion, Meloetta, Heliolisk... you get the point.
Moltres is just another of a group of offensive pokemon who as a group tend to beat each other up based on speed stats. Many, many pokemon are capable of revenge killing Moltres, or forcing it out.
Point 2:
Scouting its set is not too difficult.
This is a somewhat subjective statement, but there are plenty of effective answers to Moltres regardless of set. Lanturn, Regirock, Tyrantrum (it should have a Choice Scarf in this meta, other sets are very hit or miss), Assault Vest Slowking, and most Cresselia are good answers to Moltres regardless of its item. Rhyperior, the most common Moltres switch, is very very solid as well, only fearing Life Orb HP Grass.
The scariest a Moltres should ever be is the turn before it uses an attack, because you have to respect the damage and ability to change moves of the Life Orb set and the speed of the Choice Scarf set. Once it reveals whether it has Life Orb recoil or not, you can either force it to switch out with a faster pokemon in the case of the LO set or switch to a resist if it has a Choice Scarf. Why this works effectively for handling Moltres and not other pokemon is that
it cannot run other items anywhere nearly as effectively as other pokemon. Leftovers sets and Expert Belt sets miss out on the power of Life Orb, as Moltres has mediocre super-effective coverage and needs a damage boosting item to get 1hkoes and 2hkoes. Choice Specs sets run into the issues of Scarf and LO sets, and I guess an Assault Vest set (no one uses this shit) would lack both power, speed, and recovery.
Point 3:
Dealing with each individual set is not difficult.
For Choice Scarf sets: Keep a resist to its stabs healthy, or a pokemon with recovery who is neutral to its attacks. It doesn't do
that much damage to neutral targets. Keeping rocks up is key here, and part of the matchup. The better player will control rocks on the Moltres user's side of the field, that's part of the skill required to play pokemon. It would probably be broken if it could switch into rocks 4 times, but the fact that scarf sets are so reliant on keeping hazards clear makes them require a lot of support, and they lack the power to do anything more devastating than clean a weakened team. Faster scarfers are good here, and priority owns it as well, because it cannot switch into rocks twice if it has taken any damage at all. Hitting it with a Thunder Wave or Stun Spore on the switch in takes it completely out of the game, and Knock Off removes a lot of its threat as well. It really can't switch into many pokemon effectively because of how easily crippled it is.
For Life Orb sets: The general principles stay the same, except the "defensive pokemon with recovery" group gets swapped out for "offensive pokemon with more than base 90 speed". It's difficult to switch into if you didn't bring a good pokemon to switch into it, sure. Houndoom fits that criteria too (I'd argue LO Houndoom is more difficult to switch into than LO Moltres, due to Dark Pulse having better neutral coverage with Fire Blast and Nasty Plot threatening pokemon who sit and eat attacks while recovering) and no one is arguing to ban it. If you give a Life Orb Moltres free turns to attack you're gonna have a bad time. If you give Life Orb Heliolisk free turns you're gonna have a bad time. You have to account for it in teambuilding of course; if you want to use Tangrowth or Amoongus, you might consider adding a Lanturn so that it doesn't ravage you every time they bring it in. If you use a team that has Rhyperior and can't switch into Tangrowth, you're going to give up free kills every time it comes in and you'll probably lose. This is true for every pokemon usable in RU. Moltres is not an exception.
Point 4:
It cannot safely switch in to much.
I've hit on this before, but there are so, so few pokemon that are used in RU that Moltres can come in on without being crippled. Whether it has to risk getting statused on the way in (paraed Moltres is barely a threat) or taking a super effective attack off one of its many common weaknesses, it just doesn't get many chances. Its two 4x resists, grass and bug, aren't very usable. Grass attacks are paired with stun spore frequently, while the most common bug attack (already an uncommon attacking type) is u-turn, and coming in when they get a free switch is no good, since you have to switch out again in most situations. Its ground resist for the same reason isn't very usable, as it's frequently paired with rock-type coverage. The fighting resist is neat, but offensive sets struggle to take some resisted fighting attacks (252+ Atk Life Orb Reckless Hitmonlee High Jump Kick vs. 0 HP / 4 Def Moltres: 187-220 (58.2 - 68.5%)).
I think that those four points pretty much summarize why I don't think Moltres is broken. I'll end my post by saying that
Choice Scarf Tyrantrum is a top 5 pokemon and it makes Moltres its bitch, so that mon getting released honestly what pushed me from being undecided into no-ban territory.