I did, it's a mess. So you call every piece of content a system? Some currency too? Cosmetics matter and anima that is currency for cosmetics don't? xD
Beside battlegrounds and more world pvp goals (which of course could see more attention) we get rest content that "matter" every patch. It's not like you would got extra dungeon if character progression become barebone level&gear. Expac systems mostly take time from team working on balance (that's why I'm oppose any choices in this systems).
Btw, practically gear from raids&dungeons is dead too after expac is over (especially rings/neck that don't even have transmog value). How they "matter" and progression system that is over after expac is done - don't?
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Looks like we have catch up gear already implemented, wowhead reports treasures/quest/rares are 249 (I hope rares has fixed loot table like in 9.1) and very expensive vendor for 246 to fill gaps. No upgrade, no account-wide tokens. Why they just don't copy good systems, I don't know.