Dude you literally said you wanted torn is S rank you can't say he is overhyping Sylveon lol, and you undersell the fuck out of sylveons typing and move pool in all honesty. The great thing about sylveon is it only needs what little coverage it has, sure maybe it would like a stronger fire move but it has a good enough pool to 3hko/2hko almost every mon in the meta. Also sylveon is great against stall cores all you need is to pursuit trap a blissey or psyshock a tenta or do 40 to an aggron and hvoice straight kills the team, whereas tornadus has high risk moves, which sure are fine in most cases but they can not stack up to a mon whose STAB move is much stronger with absolutely no drawbacks, no -2, no miss, no immunities. Also BP is great for gaining momentum on the few counters sylveon does have. I get saying keep it A but your argument was really poor and you posted a ton of irrelevant calcs, as always.Ok time for raw blasphemy, Sylv is just another specs user one that notably lacks utility outside of baton pass, is restricted to a whopping base 60 speed tier with underwhelming neutral bulk, and has hilariously weak coverage, the overhype here is real, sylv has had a metagame impact but it's very limited.
Random vests are what people who do not understand how2mons slap onto teams. There has been a noticeable but not overwhelming upswing in sylv's actual counters on stall/semi/defensive balance in the form of spdefmlix/megron/arcanine/Bliss/Rade/Fatqueen/etc but these mon's were good beforehand and saw a reasonable amount of use. Sylv is never breaking bliss on it's own unless it's like... banded double edge and the pursuit wow core functions similarly with most of the tier's other top tier specs/LO AOA users.
On offense you only need to swap into sylv 0-1 times and can flat out ignore the little shitter with strong neutral hits and mediocre bulk alongside weak resists, offense can pull this off because.... 5-6 mon's on the team team are faster than a base 60 and can either OHKO or 2hit KO the little shit while living any hit. Seriously outside of TW/TR sylv is just a speedbump for HO. It does make hydrie slightly worse offensively on this archetype and limits DD gyara but you run those on HO for the defensive utility they provide not for their overwhelming offensive presence.
A rank is already overselling it.
252+ SpA Choice Specs Pixilate Sylveon Hyper Voice vs. 252 HP / 4 SpD Blissey: 216-255 (30.2 - 35.7%) -- guaranteed 4HKO after Leftovers recovery
252 SpA Choice Specs Chandelure Fire Blast vs. 252 HP / 4 SpD Blissey: 225-265 (31.5 - 37.1%) -- guaranteed 4HKO after Leftovers recovery
252 SpA Life Orb Hydreigon Draco Meteor vs. 252 HP / 4 SpD Blissey: 208-246 (29.1 - 34.4%) -- 99.8% chance to 4HKO after Leftovers recovery (superpower)
252 SpA Choice Specs Shaymin Seed Flare vs. 252 HP / 4 SpD Blissey: 189-223 (26.4 - 31.2%) -- 15.7% chance to 4HKO after Leftovers recovery
252 SpA Life Orb Azelf Psyshock vs. 252 HP / 252+ Def Blissey: 300-355 (42 - 49.7%) -- guaranteed 3HKO after Leftovers recovery
252 SpA Life Orb Tornadus Hurricane vs. 252 HP / 4 SpD Blissey: 175-208 (24.5 - 29.1%) -- possible 5HKO after Leftovers recovery (Superpower)
252 SpA Life Orb Infernape Fire Blast vs. 252 HP / 4 SpD Blissey: 153-183 (21.4 - 25.6%) -- possible 5HKO after Leftovers recovery (Stab CC)
252+ SpA Life Orb Sheer Force Nidoqueen Sludge Wave vs. 252 HP / 4 SpD Blissey: 153-183 (21.4 - 25.6%) -- possible 5HKO after Leftovers recovery (muh hazards)
252 SpA Life Orb Sheer Force Nidoking Sludge Wave vs. 252 HP / 4 SpD Blissey: 153-181 (21.4 - 25.3%) -- possible 5HKO after Leftovers recovery (superpower)
Sylv is pretty pwrful but not incomparably so while on the other hand... all of these are either not choice locked, have a much better neutral bulk/resist game, have more utility, or have a stronger matchup against dedicated stall cores, and none of them are in the pitiful hell of base 60 speed.
Sylvs unique niche as a truely offensive fairy is legit, is strong, and is worthy of A-/A rank. But most of it's perceived potency comes from... ladder adjusting to new threats at the pace of a paraplegic tortoise.