I think most damage is already done.
10 campaings out and only 1 or 2 are full at prime time on a good day.
Many people will not even make it to V10 before throwing in the towl due to the massive quest grind Zenimax has in store for them.

hate to say it but i think ESO has reached a critical point now with the free month comming to an end.
Many will not resub and many dint even reached V1 yet, let alone started the mind numbingly boring grind that is veteran ranks.

Each and every forums eso is getting teared apart from pvp to pve to leveling to class balance.
And i dont blame them.
Maybe it good that many people quit, then broken stuff gets fixed faster.