completely lost the plot

Yeah, it went off the deep end

If it's about the "final episodes" of the "final season" then that should probably be discussed here: https://moviechat.org/tt30216340

** final season/eps spoilers, in case anyone doesn't realize **

Anyway, I too was disappointed. Normally I do like political intrigue, but that is not what we got here. Just an incessant string of betrayals and inexplicably ineffective leadership. Once the military brass were gone, suddenly the only paradigm was "either genocide or we don't reproduce." Wtf? Making those the only two possible solutions makes no sense at all. Eldians could have developed a charm offensive beginning with the nation of Hizuru and worked from there! Eren's actions didn't do anything to liberate any living person from an objective perspective-- and especially not himself. At best, it was just about freedom for Ymir, which wastes his character arc and makes it pointless.

So character progressions stalled (imo at least two of them were arguably ruined), and themes got seriously muddled, as far as I could tell. Also this is going to sound random but poor Conny's mom! I hope there was somebody around who could help when she went back to being human...