Whether or not she ever returns to the level she achieved in 2012-2014, if she continues to compete at any level, she will continue to be a news item for quite a while -- the half-life of media hype will ensure that. That's the way it goes.
As for her current year marks, I am not 'shocked' that she isn't running great -- even athletes whose careers turn out to be successful long-term have ups and downs, but I am surprised as of now that she is not even at a level to get a qualifying mark for USATF indoors. I would guess that she did come into this year with some goals -- not just travel and the providing some international variety at the back of the events in which she is entered. And I would guess that one of those goals perhaps included competing at and perhaps even being competitive at USATF indoors. In her brief career, she has placed some emphasis on her indoor seasons.
As of today, she has a week to earn a USATF indoor qualifier -- if in fact that remains an interest. Otherwise, she can take a break and transition to outdoors -- if in fact that remains an interest.
At the moment, this is all pretty obvious, but it really looks like everyone involved in the decision to fast-track her into professional distance running -- including Mary Cain herself, but especially all the adults around her (parents, coaches, etc.) let themselves get more than a bit carried away with their confidence in their perceptions of her potential, and in focusing on that potential, ignoring the wide range of trajectories promising athletes take. They closed the door to collegiate running before it was ever really open, because they were all so sure she was "beyond" that level. Well, she was beyond that level at the time, but as happens more often than not, now she is "at" that level which she once was "beyond." But she -- and all the expert adults around her -- foreclosed on that option. Too bad. I am sure she is making more $$ than most 19-20yo Americans, but I doubt if Nike was foolish enough to tie up too much money in her. I doubt she is making enough $$ to make all of this enjoyable.
Her 2015 best marks -- had she been a collegiate athlete and produced them as such, would have put her at or among the collegiate leaders last year. So far this year, her best marks -- two 1500s @ 4:13.xx -- would also put her among the collegiate leaders (not at the top, but in the top several). Too bad she's not competing at that level in those arenas, rather than looking lost on the international indoor circuit.