I think it's clear as day. If you play against KeldeoCrowned then you should run a Chansey core.
And if you're Frags, you never play without a Chansey core.
And if you're Gb, then Tangela.
Really appreciate all the good discussion. It might be good to share how players prepare for Dugtrio, knowing that it can have such an impact.
For example, older metas meant if you ran Blissey, you had to run Shed Shell to prevent being trapped.
Are we running shed shell and/or counter play?
We're going to focus on Dugtrio rather than Arena Trap (AT) in this case.
Diglett is arguably a better Endeavor user with less HP and yet it gets little to no play. The only OHKO Diglett can achieve is Magnezone and it runs the risk of being outsped by Choice Scarf. Too soon to argue for a blanket AT ban.