Howdy, felt like adding to the ongoing discussion.

Keep around A-?
I feel like the competition around fighting types has gotten steep. IMO, the best 2 fightings are Hitmontop (spin + taxel) and Toxicroak (water immune + basically a dark type). Fitting Passimian means you aren't fitting one of those two guys on your team. I think A- is fine, since on one hand it is the slowest viable scarfer and doesn't outpace Beartic (436 bear and 426 pass), but on the other if you want the pivot, its better than Primeape. IMO its speed tier usually makes it barely worth considering on my builds since I don't want to be in a scenario where I need to outspeed something that a faster scarfer can but Pass can't, but I'm aware that my take severely undervalues this mon.

A -> A-/B+
With the fighting-type competition, I've felt that adding a Sneasel to my team adds less than adding a Toxicroak or a Hitmontop would. It doesn't help that Toxicroak can tech EQ to beat Sneasel-h. The speed is still nice though, and even though I think Pass is better than Sneasel I feel like B+ is too harsh.

A -> A+
This is an opinion not yet formed with the advent of Drifblim because the balloon can outspeed and wisp this guy, but that aside, there are so many games I've brought a top into and realized that I get 2-3 KOs on preview with the right clicks because spin and taxel are so free. He's very difficult to switch into, and since he can afford to run protective pads, it's also hard to punish its pseudo-stab taxel (thank you technician).

A -> A-
I feel like I have to defend Lanturn a lot when its brought up. Like sure, it has a bit of 4MSS and is by no means conventionally reliable, but there is not another mon that can switch into zard/Jolteon and generate momentum with any reliability. On the right team, a lanturn is invaluable. Now, Toxicroak makes its job harder. IMO flip turn + discharge was pretty optimized, but not being able to pivot on Croak makes that set worse, and I see it dropping but not out of the A-ranks. Like, whiscash is good but it does NOT replace Lanturn.

C+ -> UR
Now that we have croak, I want to unrank the worse option that is weak to Psychic, Fairy, Grass, Electric, and Flying, while also not resisting Poison or Fighting. Need I say more? Why would you use this mon defensively, and base 70 is a very unfortunate speed tier, underspeeding base 80s without investment and not beating jolt at +1 (as if you're scarfing this lol). I barely saw redeeming traits pre-croak, and all of them mostly boil down to it being a water type. I'll give it taxel resist, but until someone brings it for that reason I don't think it should be ranked.

B+ -> B-/B
It's definitely worse in this meta and currently rated too high, but Bonnet is not common enough to send it all the way to C. I think Polter is has more upside and is less likely to whiff than Medicham's STAB combo is to, and trev has a lot of tools outside of being a massive nuke.

-> A- or keep B+
Prankster Encore loses a lot of its value once you realize you can just attack and often 2HKO it, especially on the special side.
Saying Sableye is bad at taking special hits is like saying Lanturn is bad at checking Venusaur or Chansey is bad at checking Flamigo or some other physical fighting - it's not really supposed to. It isn't 2HKO'd by burned physical targets (and it's good at burning them), and when you build with Sableye you do so in a way where it doesn't ever have to take special attacks. I do agree that the frequency of dark types/tera dark hurts Sableye, and that all the weaknesses you mentioned do hold it back, but I think anything lower than B+ is too harsh since of the influence it has on these mons running tera dark.

UR -> C
They've popped up in tours. I don't have time to explain more than somewhat bullys lax and weakness policy.
And here are a bunch of noms to defensive helm mons that I've found less useful lately and can boil down to 'use mesp':

A -> B+/A-
I've given up on assuming Sandslash is beating any spinblocker. I only use it as a poison resistance that can KO the poisons nowadays.

C+ -> B+
I haven't seen enough out of Sandaconda to think it belongs in the A ranks or above Sandslash. It's criminally underrated right now, but that was because using conda meant asking yourself "why am I trading knock and spin for recovery on my ground type" and without Venu around I don't think it was ever worth the trade. Now, I think that it's equal with Sandslash at best, a sub-tier below at worst until I see a little more from it.

a/a- -> B+
I've found both of these to be less useful in this meta, despite checking poison-fightings. Weezing's biggest flaw is not being able to hit the mons it walls. It's best option to kill poison-fightings is Psybeam. 65bp Psybeam. That's ignoring wisp, to be fair to weezing, but you're still waiting for the mon you're checking to kill itself for the most part. I think flamethrower sets are legit, since yes I want to switch a special attacker not threatened by its stab into the physical wall with unreliable recovery, but even this innovation is less valuable than Drifblim IMO. Muk has to be running Physdef investment to not get 2hko'd by Hitmontop, and it's weak to croak EQ, and has somehow less reliable recovery than Weezing. Its two benefits are being knock resistant and able to do damage to poisons with Zen Headbutt, but they're not that big.
I more or less agree with everything else.