I do not think it is going to be the case, but the best-case scenario is that you separate mp and sp, like in DAI or ME. But usually, only the devs with big studios and a long bucket can do that.
I agree that when you try to make your OC a MP experience, you have to make some concessions to make the game pace more fluid and you have to cut some things. And forget about to stop talking to npc, reading books or crafting because you make the other party members wait too much.
In DaO2, for example, the banters between party members and involvement in conversations were minimal. They also changed the thievery mechanics since the beta. In beta the guy you robbed call his friends and they search for you as a mob, but in the final version only the robbed person does that, and it is very easy to evade.
Well right. Exactly. So if the other players are not going to want to wait while you spend as much time as you want exploring everything and reading everything and talking to everyone, etc., and as a result your players are not going to do any of that in the game, then what is the point of spending time and resources creating and including any of that in the game? This is what I fear will happen to an RPG that is co-op/MP first and foremost.
People are always surprised when I tell them how many hours I have spent on just a single playthrough of the RPGs I like to play, usually more than 200 hours and often more than 300 hours. This is precisely because I love just whiling away my time on just exploring what the game has to offer. Heck I even read every entry in the encyclopedia or reference section of the game if such is provided, and can easily spend hours just fiddling with the equipment distribution among my party. But for me to be able to do this and get this level of enjoyment from a game, the game must provide to me all of this content and material in the first place.