I think the problem is Ion is a highly analytic person. Hell, he seems wayyy more suited to be an engineer. (Trad - mechanical, chemical, etc) Now he’s the ideas guy and has been for two to three expac. It doesn’t work with his mind. They need a new ideas guy. Ion clearly can design raids - the most analytical of processes outside class balance. The problem is fitting everything to a rigid structure - almost an equation each time makes it fucking so goddamn predictable.
WoW's been bleeding subs since Cata, when they killed off the social element of the game with cross realm instances, guild perks (destroying entry-level (social) guilds), raid finder, etc.
Most people don't care about gear or item levels / sets for their own sake. Those carrots only matter if you can show them off to your friends and gain status in the community. They reflect the utility that you can bring to your guild.
WoW designers have done everything they could for ten years to remove barriers that forced community interaction. Removing those barriers made the game easier to play, easier to experience, easier to get bored with.
I spent a little over a decade as an MMO addict in EQ and WoW, playing 6+ hours a day with long gaming sessions on weekends that lasted as long as I needed to keep playing. Was it for loot? Nah. It was for my friends.
I still remember spending three months of my summer vacation sitting at a computer 16 hours a day, in the same zone, sitting on the side of a fucking mountain not playing the game, and having my brother play the other 8 hours a day just in case someone sent me a tell and I didn't respond in time to keep my spot in line. All for some stupid MMO item. The item looked like a limp dildo, it's stats were shit, and I never replaced that item before I quit the game 4 expansions later. What was the item? The Everquest 1.0 Cleric epic.
My entire guild woke up at 4 am to kill that fucking dragon, and we wiped. So I had to do it all over again. When it was time to turn in the final quest, everyone in my guild was there to see it.
WoW is in a death spiral, and the Devs are unwilling or incapable of recognizing the cause. They're selling a single player game when what made WoW popular were the MMO barriers they destroyed.