Ubisoft should make a option to purchase this Exotic weapon, as a add on content. The other option would be they can also lock it behind the Legendary missions.
A big NO for pay-to-win. Regardless of whether the Eagle Bearer or the Big Horn are valuable as weapons pay-to-win transactions would be a disaster for the game. Boost to level 30, beat Keaner, buy all exotics, and game over. No thank you.
Considering that Ubi's keeping the game alive only with the intent of improving monetization, I would not put it under them to create such P2W options.
It's just another weapon, there is plenty of weapons in the game that do just as good, if not even better.....and even if they don't it would be very small marginable difference.
Can't understand this obsession with the EB and other stuff locked behind a raid.