My initial enthusiasm, created by Zenimax claims this was something other than a typical MMO, that made me sign for Beta was quashed by the war and character restrictions which are totally false constructs and purely to designed to create a 3 sides war for mass PvP mega raid to attract current MMO players.
Then I get a Beta invite and discover what is I assume standard for quest based MMO's which is a single player game with bolt on multi-play. Only trying other MMO's long after launch it has not been as obvious before.
We are all the same hero following the same path (NDA example we are all the Dragonborn).
This poor design shows a lack of imagination, producing a one story fits all world. Fine for a single player game but for multi-player it's inadequate and disappointing.
The result this inevitably brings is a follow the crowd to next objective, the crowd may get thinner over time but all follow the same path.
Combined with the "Endgame" mentality, it's supposed to be a world where life goes on with or without your presence. Individuals end the world should never have an Endgame. New content and areas produced and old areas changing,
A world evolving, never ending.

This style of Single player focused format in a multi-player system with an Endgame mechanic (raids) and dominated by out of game guilds, commonly referred to by the emotive term "WoW clone", often used purely to provoke a predictable reaction, but also used as abbreviation. I consider "Typical MMO" or just "MMO" as a less emotive and more accurate abbreviation.
When "MMO" users say they want something new and different, in reality they mean style and not substance. This is evident in the many "It must have ..." posts. In contrast those who want an online game but don't play a current "MMO" are more likely to say "It must not have ..." to exactly the same point.
These are opposite attitudes to the online experience, the basic core of the "Sandbox" view is create a world with few restrictions and many options for advancing with no right or wrong path, no player is special and you improve skills and equipment to advance not levels and health. Baaically a stabbed heart kills all and abilities dertermine whether you are stabbed and where.

Current "MMO's" are played by a limited (meaning not increasing) number of gamers that has remained about the same for years and it will stay that number however many "MMO's" emerge.
When TESO was announced Zenimax said they would be different and the Elder Scrolls player base gave them the ability to create a new and different online experience. Sadly, they took the style over substance option.
Any potential online game that tries to convert "MMO" gamers to their game is just diluting the genre and this is evident in the many who don't even look at the next "MMO" as a style change is not what they want.
If this wasn't Elder Scrolls the non "MMO" TES gamers would not have even looked twice at it.
The worst thing is not many online games have the advantages this has so game publishers are unlikely to even try a new approach.

So the next advance must be backed by gamers using crowdfunding, Star Citizen although Space Sci-Fi game shows it can be done.

The next big online game is unlikely to even call itself a "MMO" as doing so limits it's appeal to the non "MMO" gamer.

As an observation I read a post that said
"I will be a blacksmith, you can find me at ..."
That says to me TES community is good, the game?

If you are a TES and "MMO" fan this game is for you, it's what you want.
However TES fans who have already rejectd "MMO's" will not play this as despite the name it is just TES "MMO" not TES Online.
It's success or failure will be judged on how many "MMO" users convert to it.
That limits it's potential user base even before it's released.

Finally, as with all generalisations there are exeptions to these groupings. Finding one does not make the rule invalid.