I'd say the biggest mistake is that yes y1 stuff shouldn't be as good as Y2 specifically the raid but, to make everything y1 worthless only makes their world smaller with each addition and no incentive to play any of it when they could make at least an item or two worthwhile getting from each raid for some reason. No they shouldn't be better but, that doesn't mean nothing should be relevant anymore which is what they did. Then players only have a small amount of content worth replaying which always leads to everyone getting bored, pissed, or quit with the exception of some. Great MMO'S keep everything worth doing whether it's for new players or putting exotic equivalent items in older raids so there's a reason to do it. In the perspective of people that got done around TDB or How you now run the quests to complete those expansions while at the same time having TTK quests available which gives far far better rewards and starting light on them being in most cases 60 points higher than the older expansions. So the expansion quests you run but, they're not fun, worthwhile, or exciting because, you just junk everything you get from them. It gets boring and in cases like mine, I haven't even completed most of TTK exotic bounties or new quests because, everything just got boring from the enormous grind you do mostly for nothing at all other than to complete the quests and get thrm off your quest list. Doesn't make sense, they just made it more boring somehow.