First, not to be nit-picky, but games like The Division, Destiny, and Warframe aren't MMOs. Yes, there's a metric-fuckload of people who play them, but the actual game format is either PvP in queue or open realm, or PvE Single/Squad co-op.
That being said, I wouldn't mind having some form of Borderlands media with a squad based arcade feeling, ala Lost Planet 2 or Warframe, but I have to agree with the others in this form that Borderlands 3 should be a Borderlands game. Cost and (IMO, bad) gameplay aside, the MMO-scape is already saturated. I don't think that "Borderlands the MMO" would unite BL and MMO fans as much as disinterest people who are fans of one or the other, and not both.