How so? Give reasons and examples.
A series artistic integrity is relative to it's games, and it's games to its genre. To subvert or to replace the genre, is to subvert the purview of the series. So taking this into context, if you are to take a successful series of games that are defined as single-player RPGs, and throw in a game that removes what defines their integrity, the single-player aspects, and replace it with multiplayer aspects that are not only untested in this particular series, but have been shown in other cases to render null and void the rest of the franchise, is to possibly corrupt the very artistry that has defined the series.
I doubt this will do anything to change your mind, so perhaps this is a waste of my efforts, but it may answer how it might nullify the depth that defines the TES series, keeping in mind this is from an artistic point of view, viewing the series as a body of works, rather than a series of games.