I believe ED was NEVER planned as single player game; and the proof is that you need to be online even to play solo....and that the functionality of offline play, was removed.
Now, what an MMO is, can be interpreted in various ways, but the most commonly accepted are
1) n number of players, which share an instance
2) You need to be online all the time
3) The area where your avatar exist, is usually pretty large
Then we can argue that Battlefield or COD are MMO or not; this is debatable; but if you want to make an online game, either you go for the ad hoc connection approach (what you see in 99% of the games, where people play offline, and if they want to go online they go in the lobby area of the game, and groups are created), or you go for the MMO.
Traditionally an MMO is easy to represent when you talk about an RPG or action RPG based mechanics....Diablo 3 has been called MMO by some, but obviously it is not, in my opinion; but Lord of the rings online, Star TRek online, WOW and the ton of other similar games, are clearly marked as MMO.
Now, ED....obviously it was targetted to users interaction, but they messed up every single thing, because the genial minds behind the design of the game, thought that you can just get Elite, make the map 3d; create instances and put players in...all done, we have the MMO.
Sadly, reality is a different beast: due to the size of the map; there were limitations to the number of players that can fit in; we are talking of 400B systems, each one instanced, which put a burden on servers to where to locate players.
Since the beginning, I believe I saw at most 8 people in the same instance with me; and this improve in SC while you travel in a system, but mainly because there is just void around you. Create a multiplayer game is hard, make one with such scale for the maps, is even harder, and I am glad that they were at least able to put together a semi-working instance system.
But this is not what many were hoping for....they were hoping for a hub; you get off your ship; interact; shops, meet players, and then go out to explore or do whatever the game allow you (I won't even touch the topic of the activities, that's a whole different can of worms to not even look at). Instead they were given a game where there is nothing around you; where instances are basically all the same, with minimal variations, where the interaction happens because someone pull you out of SC, or just randomly shoot at you, while approaching to a station. Wings tried to put some glue, to give a purpose to be online, same for the common target missions, where players collaborate; but we are far from the real implementation.
I can't consider ED a real MMO, as WOW, but nowadays, if you want to make a game, it must be multiplayer, and the way in which ED implemented multiplayer is neither a fully fledged MMO, nor a generic offline game that allow ad-hoc multiplayer.
Is this a good or a bad? That's up to you; whatever you like, enjoy it, otherwise you can only make noise on the forum, or hope to win the lottery so you can either pay to make your own game as you want it, or buy Frontier and fire all but DB, and help him to make a real MMO as in the original intentions. Right now what we have, is a product put out of the door in a hurry, to anticipate on Star Citizen craze. Unless ED become better by the time that SC is launched....I still hope for a change, although what I saw in the past year and a half, push me to believe that this chapter is done, money has been spent, people paid it, and that's all. We will get updates, but you can't change the foundations of the game. Enjoy the game or find something else...that's the sad truth.