See, we've thus far been given no reason to believe that we won't see a ton of familiar alien species, familiar technology, familiar abilities, familiar design, references to the past in the Milky Way (likely before the ending fiasco, of course) - in fact, I think the chance of that not being the case is vanishingly small. Which is why I don't really understand the trepidation about it unless you have a very intense personal connection to the original trilogy (which, granted, is a thing).
To me, it's like going from Fallout 3 and the Capital Wasteland to Fallout 4 and the Commonwealth - except, in this case, I like everything about Mass Effect more than I ever liked Fallout.
Except this is a new galaxy. That right there means unfamiliar technology, as it will take a rather large deus ex machina (or an equally large handwave) just to get there. Or this is the very distant future.
New galaxy also means new completely new locations. No Citadel, no Omega, no Feros, etc.
Also new races. Yeah, there'll no doubt be crew members of familiar races and all. But every single representative of those races will be on whatever "ark" this is. There will be no Migrant Fleet to visit Quarians. No batarian world to visit. As it is, the shot of a krogan in the teaser is so brief you have to go through the video like it's the Zapruder film to see it.
And abilities? THe only thing we've seen is generic-faceless-dude use an omniblade. Without that, it could be any game.
I play Fallout, but I'm not quite as deep into the lore as others are. But you know what, there is grumbling about how Fallout 3 and 4 aren't "really Fallout" (compared to Fallout 1, 2, and New Vegas) How the East Coast super mutants don't resemble the original super mutant vision. How the Brotherhood is too friendly to outsiders. How the drug Jet now seems predate the Great War. And yeah, how the Institute doesn't really fit the setting.
Who's actually confused about whether this is a Mass Effect game? Are you? Really?
If so, why? You can't actually think that, say, biotics won't be coming back.
It's got the "mass Effect" name in the title, so of course it's going to be a Mass Effect game. But who's to say if the similarities will go much further than that?
If I saw this teaser on tv, without foreknowledge of what it was, I'd have a hard time identifying it as such.
Compared to, say Dragon Age's FIres Above trailer, also released over a year before release, which had familiar names, faces, uniforms, even a qunari.