Galarian Darmanitan doesn't exist in BDSP and as such is irrelevant as a demerit against ice in the present metagame, especially as gone are the obnoxious defensive threats such as Ferrothorn that generally wreak havoc in its absence. The closest thing to Ferrothorn now is Forretress, which as of now isn't very good and has no recovery. I don't think Ice is quite mid tier, as it autoloses to both Fire and Fighting whether Blaziken is present or not,) struggles with Steel, and has a hard time against Dark if the Ice player is not running SD Weavile (which is a subpar set on Ice.)
(to be cont)
- Many if not most ice builds will be running Abomasnow. Ice's viability in the metagame is contingent on its role as anti-meta. This makes Abomasnow a no-brainer not just due to Grass coverage but also its ability to set Aurora Veil and hail chip ensuring that Weavile's Banded Ice Shard is always a KO against Latios.
- Metagross is a threat but finds itself in heavy competition with Jirachi for a teamslot due to the latter's far greater all-around utility as a pivot as support mon. As a physical attacker it is outniched by Medicham (no one competent should be running Gallade on Psychic –– no one competent will ever be running Scarf Gallade) due to Medicham's far greater utility against Dark and Steel, as well as Medicham's similar access to Bullet Punch and elemental punches at a higher speed tier.
- "Without Shell Smash cloyster, good luck trying to out offense scarfers. Even then, scarf latis outspeed you." Ice runs not one but both of the viable Ice Shard users in the tier. Beyond that Weavile (if it is scarfed) outspeeds both.
Assuming you run band weavile and mamo:
252 Atk Choice Band Weavile Ice Shard vs. 0 HP / 0 Def Latios: 224-266 (74.4 - 88.3%) -- guaranteed 2HKO
252+ Atk Choice Band Mamoswine Ice Shard vs. 0 HP / 0 Def Latios: 260-308 (86.3 - 102.3%) -- 12.5% chance to OHKO
252 Atk Choice Band Weavile Ice Shard vs. 0 HP / 0 Def Latias: 204-242 (67.7 - 80.3%) -- guaranteed 2HKO
252+ Atk Choice Band Mamoswine Ice Shard vs. 0 HP / 0 Def Latias: 236-278 (78.4 - 92.3%) -- guaranteed 2HKO
Also, even with hail, the only OHKO is band mamo vs latios.
Here is why you are wrong when you said jirachi is better than metagross. JIRACHI LOST IRON HEAD. I don't care if it can pivot. Iron head gave jirachi the steel type move that constitute the scarf uturn, as well as thunder wave set. Without its most powerful weapon, jirachi has no niche on psychic beside specs/scarf special attacker with flash cannon as the best tool for ice. Metagross has band bullet punch which does heafty amount to a lot of pokemon. In addition, it has meteor mash which can give it an attack boost. Plus with metagross's higher defense allows it to take a few more hits. The only advantages jirachi has is support in the form of wish, uturn, and healing wish. With a hyper offensive meta as this one. Metagross is definitely better which makes ice a lot worse.