Its stated in my post.
The easiest example to run off is WoW. Have you ever tried to get into a Raid or dungeon run at later levels in that game?
Its not so bad at lower levels for new players, but as time goes on, they start to become alienated, because of GS, DPS meters etc. Because of this alienation, they are forced to follow the same trend & using these tools.
They then begin to fall into specific class categories to get the most out of their DPS...so class variation become almost non-existant.
Then they start to act the same way to lesser players/ new players and the trend continues.
With so much available variation in even a game like WOW, players have dictated its decline & all because of addons.
When I started playing Dungeons with friends, we would figure it out as we played. We didn't "need" the best gear, best DPS or beat heals.....we just needed to play well together. Timing, covering each others failings/mistakes using class skills etc. Of course, now & again whatever we did, it was impossible & required better gear....but that is learned as you go. We had fun and used our class spec's to their best.
Once the crap started with addons, it became nothing more than meta-gaming. Hitting certain marks before even considering trying to have fun. And when we entered to have fun, we were left sitting in specific roles of what to do & what not to do which restricted gameplay & fun.
Later Blizz starts designing bosses to take into account the changes players have made to the game via addons.......and it just stopped being fun.
And you want to do the same thing with ESO?