I haven't played FF12 and disliked 13 but I enjoyed FF13-2, so all is not lost. I actually like the direction 15 is going so I'm hoping the fans will come together again and it will be exciting to be a fan once again. It would be a shame to let the series die, even if most of the original team has left the developer studio.
Anything bad can be used for good, FF draught has inspired me to create my own series and survive.