If it launches out of EA without some form of native support for a party of 6, it will be really hard not to feel that our EA feedback was basically ignored.
Whether or not this should really be the test case for how well they respond to EA suggestions, I think it will nevertheless end up being just that. Mainly because its so cut and dry, relatively straightforward to accommodate, and a very easy thing to point to. Either peeps will say "look! See how they totally listened" or "look! See how they didn't listen." And it will probably be emblematic in that way. Whether what so many people in their EA asked for week after week was taken up or not. It will color the whole "You asked! So we listened" angle, and likely serve as a bellweather for what kind of official support we can actually expect for other feature requests and EA critical feedback, vs how much the game will just be dependant on unofficial mods for its afterlife.
They can leave it to the mods, sure, but that will have knock on effects.. it would also signal to me that I'll probably have to wait another year or two even after it comes out of EA for some rogue gang of modders to do the hard work, build and balance the things that the team of pro devs should have just built into it in the first place. Some unpaid modder or team of modding enthusiasts will have to do the heavy lifting, and while I hope they can pull it off, it won't be the same thing, or engender the same kind of goodwill or sense of being heard by the powers that be.
I worry that the party management and movement control issues that I'm constantly fighting with right now will just go unaddressed, and that they will use their smaller "tighter" party concept as a cop out. Giving us fewer companions and just sticking us with a bunch of followers or random friendlies we can't control, because its simpler than fixing the pathing, targeting, UI, and combat scaling that would be needed to make a full party of 6 work well.
I still hope they're keeping tabs, and that interviews given in September before EA even launched aren't the final word on this one.