I just want to say that I stopped reading when the WW2 shenanigans started and I heard the series was ending soon so I read through this thread instead of rereading and I think I made the right choice.
YMMV on this point. This thread is pretty negative on all the post time skip stuff, but I, and others really love it. Depends on why you were reading in the first place, and which characters you liked, and if you're open to allowing our Lady and Savior Pieck into your life. It's never been a series that was afraid of putting a fan favorite on the bus when they weren't needed. If you liked Reiner, Jean, or Annie; or wanted to know more about Zeke, and the world at large, then it's a must read. If you somehow thought Eren WASN'T going to pull an Anakin and become the tortured villain by the end, or were a huge Historia stan, then you might be better off skipping it.
Not sure what people were expecting from the ending of this Manga/Show. It's always been dark, but weirdly idealistic. I mean, the first Trost arc was ended with saving the world (inside the walls) with the power of friendship and dickless flesh mechas, so I don't know why people are offended that it might end the same way.
Right now, if it sticks some kind of landing, it feels a lot like Return of the Jedi to me. An ending to a great series that has some extreme high moments, like the throne room confrontation, but also was ruined for some people by including an entire tiny teddy bears of war subplot.
At least, one way or the other, we're getting a line drawn under it. We're not going to keep getting jerked around forever like Berserk, or see the series devolve into weird comedy trannies like Vinland Saga.