I think this approach of focusing the EA on evil playthroughs is not a good strategy for the game. It runs the risk of making the evil path default for the game, because that's what will get all the iterative improvement attention. Even the good aligned companions won't show until after EA, and so won't benefit from that iterative improvement. A good EA strategy would allow a representative slice of the game to be iterated and not just one particular way of playing the game.
I don’t think they’ll be focusing on the evil path throughout EA. More likely they have things they need to test early on and don’t want 90% of players not trying them.
They probably want to check things like their quest system being robust enough to handle people doing random horrible things, or that party dynamics don’t fall apart too easily when populated with the biggest arseholes, etc. I imagine it’s more challenging to get to work than a party of super-friends making all the good choices and not trying to sabotage each other.
There’ll be plenty of people just doing whatever they want anyway, but if I join, I’ll probably go along with requests to try things they want testing.