I completely agree with your points. I can theoretically see an outcome where Webs doesn't end up destroying the meta, however I cannot see one where the solution doesn't consist of increasing both this tier's teambuilder strain and meta centralization to an even greater extent than it is currently at now.
Despite what it may have originally been intended for, Ubers hasn't—on a functional level—been regarded solely as a banlist for broken OU Pokémon since Mega Rayquaza was initially exiled from the Standard format back in ORAS. We do not have to put up with unbalanced, uncompetitive, or unhealthy mechanics (within reason) if they are actively damaging the game, anymore. What good is it to preserve the old guard's "image" of Ubers as a competitive cesspool with limited to no bans if doing so causes its very own playerbase to actively suffer from it?
Perhaps if Webs was temporary—or benefitted all reasonably offensive Pokémon equally I would consider voting dnb, however in practice, the only thing that it tends to do is make Pokémon that were already high tiers and/or constricting, even worse.
Perhaps for many competitive players, meta diversity is not an object so long as they can continue to win, however as someone who views this franchise not from a top-down (i.e. joining the game for competitive reasons and subsequently liking Pokémon according to their expediency), but from a bottom-up perspective (i.e. trying to get good because I grew to care about the franchise over time): I cannot justify voting in a manner that will result in a meta that is fundamentally antithetical to my beliefs or the identity of this franchise as a whole.
I am all for sending little timmies and their unserious Charizard teams running home: we don't need that kind of unserious faux-diversity wasting the time of people trying to actually improve—however when genuinely usable Pokémon end up being discouraged—or when questionable Pomémon end up being forced upon teams because the alternative is getting 3-6'd by Webs: we really should take the opportunity to deal with the disease while we still can.
If you have not yet settled on a stance and are reading this: please consider that Webs does not leave any significant positive impact on the tier. Even many of the dnb arguments largely come down to it simply being manageable. If your house was infested with pests, would you really not call the exterminator simply because they weren't "bad enough"? At best, Webs can be played around at a price. At worse, it is actively degrading the player experience on the ladder and encouraging degeneracy.
While I agree this is the most reliable lead set for Deoxys-S to beat Smeargle, playing this matchup is also incredibly frustrating without any attacking moves. Nuzzle can completely screw over the matchup thanks to paralysis. If the opponent is running Moody, a speed boost can mess up the matchup. While this isn’t common anymore, if they’re running Stone Axe, they can force a net positive trade in terms of hazards. If you do choose to run an attacking move, you lose the ability to stack double hazards. When I used to spam HO using this set, the greatest frustration was always playing a matchup into webs where yes, you could somewhat reliably lead against Smeargle, but was still giving the webs team a safer matchup.
Bumboclaat already mentioned Mega Diancie’s unreliability without already pairing it with a Defogger, especially given how it's reliant on not getting out played. However, not only is it unreliable on bulkier teams, it can be tricky to utilize as a lead for HO teams too, as your team needs to be sufficiently capable of switching around Zacian counter leads, which is even more challenging for HO. Thus, while Mega Diancie HO can be very solid (I actually used MDia HO team for reqs), the consideration of being able to consistently perform can be challenging to deal with, especially since your options as an Hazard Stack teams are further limited by the fact that Mega Diancie will usually never get more than a single stack of hazards up.
+ 
While I can’t speak to utilizing Primal Kyogre as a Yveltal answer, the setup of Ho-oh and Fezandipit has proven to be relatively effective. However, it is further constraining for many of the balance teams that actually want to run Fezandipit, as the go-to defensive core with Ho-oh is GHAZ, which already has 4 Pokemon in it. After a fifth, you have to begin considering solo breakers and sweepers, which ends up constraining you to a relatively short list of Pokemon like Deoxys-A.
After running around with Bumboclaat’s Defog Mence team a lot, I firmly believe the team is good. However, even then, there are some flaws that, while not incredibly glaring, do detract from the team’s ease of use and matchup consistency. Furthermore, while Bumboclaat provided Defog Mence with an incredible showing on this team, Defog Mence has also only had a good showing on this team. While it does its job, Mega Salamence is also extremely niche as a Defogger.
Yes, its Rapid Spin is pretty consistent at removing Webs. The thing is, Terapagos overall is pretty bad. You can use it, but do you want to use it? While Terapagos isn't entirely useless into other matchups, it often a very much sub-optimal choice outside of HO matchups.
I actually do believe Iron Treads can be explored more as a lead, but at this point in time it can hardly be considered real. It's only going to set up a single hazard and isn’t particularly useful outside of the HO counter-lead scenario.
I am genuinely curious if anyone involved in the tier considers this Pokemon remotely viable in the tier with a straight face. Yes, it has Magic Bounce, but its problems are extremely stark.
Ditto is good, but it certainly can be played around by HO structures as a whole, faces team building constraints, and has a middling matchup into most other teams.
