Because it's set far away from the established Mass Effect universe and is probably going to disregard everything that was built up across the 3 games. All because Bioware f***ed up ME3's ending and now this is the only way they can continue the franchise
I'm stucked in a time loop!!! It's 2012 all over again!!!
Seriously, it's been over 3 years, let it go. Prolonged whining is unhealthy.
And funny how a player "knows" what exactly ME is better than ME's own creator
It's like telling Hemmingway how to write a story about old fisherman 
Anyway, hold your horses, rangers. It's a freakin TEASER. We haven't even seen gameplay footage yet and many already decided the game is ruined? Ahh the unbearable optimism, heartwarming isn't it.