Kyurem or Gliscor are hardly the biggest issues on the ladder imo. Especially considering they pretty much check each other. I also dont know why people even dislike stall this gen. Its barely viable.
Im around 1800s playing mostly stall because it has some of the most consistent lines and even then its basically impossible to gameplan against the different variations of HO that is basically the entire ladder now. I played for about 2 hours today and Id have to say 90% of the games was Samurott/Ghol/Gambit/Moth/Ground/sweeper shells.
I wouldnt call Samu broken necessarily but it along with Ghol can put so many teams in terrible situations off the rip. Plot Ghol with Psychock also destroys stall, necessitating a tera dark from Chansey just to not get instantly swept. Then the omni present Gambit can finesse wins out of nothing far too often. I initally was running speed creeping corv to deal with it but it would either get 5 fallen and go to the casino to fish for a crit, or have some odd tera that means I cant beat it. I eventually got tired of it and used to 220 speed corv with rocky ID/body press/roost/reflect.
This is all to make sure I dont lose to this one thing. Anything else is liable to lose to a crit, tera blast, dark/glasses etc.
And thats one pokemon from these cooker cutter HO shells. I can understand why people are primarily climbing with that because trying to defensively check shit is very difficult, so why not just try to strike first. Then get reverse swept by Gambit lol.
TLDR; HO in general is still king and I dont think Kyurem really is that big of a deal. Its just another setup sweeper, or easily checked by your special wall of choice. Especially with the ubiquitous nature of hazard stack/HO teams