An exhaustive analysis of Dugtrio
So finally, someone asked a question about Dugtrio. Due to me being called a biased scumbag by a confidante, I feel that I need to type this. This post is going to be completely factual and realistic, I think I have covered the main weaknesses of Dugtrio in this post but I probably did miss out a couple more. And before you ask, I have used Dugtrio! With that being said, let's get into it.
Dugtrio is an extremely difficult Pokemon to build around due to its subpar stats, not so good typing and in particular in regards to needing to still check Xerneas and Kyogre-Primal. I'm just going to list some Pokemon combinations that would be necessary to go with Dugtrio, and you'll see the issue. Dugtrio + Necrozma-DM + Ferrothorn: Glaring Swords Dance Arceus-Ground and Marshadow weakness! Dugtrio + Groudon-Primal + Arceus-Poison: Serious Ground-type weakness! Dugtrio + Ferrothorn + Arceus-Poison: Not much of an issue, but Swords Dance Arceus-Ground can trample this pretty easily. And if you're build different, you might also run Stealth Rock on the Dugtrio, but Arceus-Poison + Ferrothorn cores want to run Stealth Rock Arceus-Poison and Spikes Ferrothorn, which is perfect, making Dugtrio irrelevant. Even though Dugtrio traps Groudon-Primal, no one will play so loose with their Don if they see an opposing Dugtrio. A cute double to Marshadow and boom, Life Orb Pursuit would trap it easily. Coming back to the cores, they can be relatively weak to Arceus-Ground if the Ferrothorn is chipped, or if it's Swords Dance. So the point I'm trying to demonstrate is that it's hard to make Dugtrio partner well with other Pokemon in the metagame, making it much less applicable to any team, except for some niche BO builds. I hope this point makes sense, it's slightly more complicated than the other points I'm going to make so if you do have any questions come and ask.
Lol. I'd rank Dugtrio among one of the worst trappers, and because of some good reasons. Apparently even with Adamant, Tectonic Rage just misses on the OHKO on 248 HP / 0 Def Groudon-Primal. Hilarious. I'd have had liked it way more if it actually KO'd a Groudon-P, but god it's so awful lol. Same is with SpD Necrozma-DM, you miss out on the KO and it can heal off the damage with Morning Sun, and then unless you get the god rolls, Earthquake won't KO it, and it's just gonna heal off again. This is just trapping and weakening, not trapping and eliminating, which is what Dugtrio's job is. Arceus-Poison is apparently the only thing which can get KO'd, but as I've said playing rough against a Dugtrio MU is like suicide. Secondly, if you ever compare Dugtrio to other trappers, you'll see why it is one of the worst. Gengar-Mega has some actual niche than missing on KO's and getting KO'd in return, and can revenge kill some much more threatening offensive threats like Necrozma-Ultra and Rayquaza-Mega. It has some feasible STAB options and isn't limited to one move (which also takes away the Z slot, something better fitted on Necrozma-DM, Necrozma-U, Marshadow etc.), and has more utility outside offensive trapping, as a Perish Song trapper or stallbreaker. Marshadow is one of the best late-game cleaners in the metagame and can put immense pressure on the opposing team, especially when paired with Rayquaza-Mega. Actually Marshadow and Dugtrio aren't comparable and it'd be a crime to see them alike. Gothitelle is another trapper, albeit rare, and personally I love this mon. It isn't limited to trapping three mons like in Dugtrio's case, and can effectively trap almost every SupportCeus form, some Zygarde-C sets, non-SD SpD Necrozma-DM, Ferrothorn, Chansey and Lugia among more. It isn't deadweight unless you get an HO or Vanilla/Fluffie BO matchup. Again to Dugtrio, it's a setup bait for things like Rayquaza-Mega too. Unless you wanna sack and go Memento on the opposing Pokémon, you're just inviting them to setup and then, potentially, sweep. It's also useless against Lugia Stall (unless they play bad with the SteelCeus lol), which is pretty common on ladder if that's what you're asking the question for, and is deadweight against HO. Dugtrio's trapping niche is so ridiculously small that I can laugh a whole day at it.
Overall, Dugtrio isn't very bad per se, it's useable, but I don't really think that it plays a big enough role with a big enough niche to be warranted a slot in a team. It's usage is very, very narrow and specific, and maybe that's why it doesn't even have a rank in the VR's. Another small thing to note is that good players like Skarph, Zenithial, PG and me have used Dugtrio in the past but we never even mentioned it, which might just mean that this Pokémon isn't that nice. Hope this wasn't too long lol, I tried to make it concise but looks like I love typing.
Hope it helped!