I've said it a million times and I'll say it again: get good. Cincinno mill is, in your eyes then, the BDIF, buy a long shot, unbeatable, oh no, I can't win, I guess the first Sword & Shield regionals will be filled with only Cinccino mill, look at that, all the top 8 slots are Cinccino mill, nothing else stands a chance.
Correct?
No?
Yeah no, it's far from broken. I don't even play standard much and barely keep up with it, but if I just had to guess, it's not nearly as broken as you're making it out to be. There are probably multiple ways around it. Playing conservatively. Maybe teching your own Oranguru. Milling the mill deck (as seen by Tablemon's playing of the deck, but tbf he was very new to it. Tbf in that regard, he is a good player, and should probably be able to understand the deck's weaknesses fairly quickly.). Little bit of Marnie, etc.
Again, I don't play standard, but I seriously doubt it's that good.