When in fiction it is possible to influence the past it's almost inevitable that some plotholes will come out. This choice by Isayama, foreshadowed or not, is a questionable for sure.
But, on his defense, i think it was a smart and exciting way to use the titans/path lore to finally reveal how Eren was never anyone's puppet, he was master and literally weaver of his own destiny all along. Well not that it was a surprise, but it was still a necessary aspect of the story that needed to be addressed. And finally the memes and also the people who really believe Eren has been brainwashed will stop lol.
So, yeah, it's a resolution that stirs mixed feelings, but i don't think it's as bad as some readers here make it out to be, it has both his pro and cons.