I wouldn't say that. Honestly, I would say this game will have too much in similarity with WoW aside from they're "in" the MMO space, sort of, and they're RPGs. I think too many people jump to the conclusion of what they expect when they hear the "MMO".
My understanding is that it will work like you will have your skill trees like conjurations, destruction etc. You'll also have your weapon skill trees including healing staves and destruction staves to level through. And on top of that you'll have your world skill lines like the Mages' Guild skill line.
If terms of how different the game will be from TES, I imagine it to be on the same lines of what Skyrim was to Oblivion - that level of difference in the class system. To elaborate on that in Oblivion you didn't have perk trees (don't take that as me saying there won't be perk points because there will be) and you have lots of pre-defined classes like Bard, Assassin, Agent, Acrobat etc. In Skyrim you did have all those pre-defined classes which meant it was more up to the player to get imaginative with their class.
I'm hoping in TESO that the developers won't have a tooltip when you put the crosshair over a player which says: "This player is a dragonknight" because that won't necessarily reflect the player's combat style later into the game.
Yes, you can eventually have a jack-of-all-trades character if you so choose. From my understanding there is no complete need to complete every skill tree if you don't want to do that on that one character.
Don't go in expecting it to work like Skyrim because each game in the single player series behaves differently.