WARNING: The following contains spoilers for Attack on Titan Season 4, Episode 22, "Thaw," now streaming on Funimation, Hulu and Crunchyroll.
As the larger world of Attack on Titan is all but doomed, there was also chaos to spare on Paradis Island as a result of the Rumbling. Eren Jaeger made a bold, dramatic announcement that he was going to annihilate the outside world to protect the Eldians of Paradis Island, but he didn't even look back at the devastation the Rumbling wrought upon Shiganshina, much less do anything about it. The destruction of the Walls hurt and possibly killed scores of people, Zeke's Titans were still on the loose, and Eren's stance on the situation in Shiganshina appears to be along the lines of "good luck with that."
For someone who loves his people so much that he'll destroy the entire world to protect them, Eren left his friends hanging as he lumbered off with his army of Colossus Titans. Season 4, Episode 22, "Thaw," had major nostalgia as Mikasa, Armin, Jean, and other members of the Survey Corps and Jaegerists fought off an attack by Mindless Titans inside the city. To their credit, the soldiers quickly and efficiently did away with all of Zeke's Titans thanks to Thunder Spears, but why did they have to fight at all? Given everything else the Founding Titan is capable of, it doesn't seem like a stretch that Eren could have killed the Mindless Titans or even turned them back into humans.
Armin Arlert tried to argue that Eren surely would have turned Titans back into people if he could have, but even he didn't sound like he believed that. While Armin and the others haven't really had time to figure out how they feel about what Eren has done, Armin didn't seem to be on board with an actual genocide. If Eren would destroy the world to protect his friends but won't help his friends out of a mess he created, it begged the question of how important these "friends" actually were to him. The Rumbling may be more about Eren's personal vendetta against the world more so than protecting Eldians.
Eren's pledge to Eldians was to protect all those currently residing on Paradis Island, but even those Eldians were not spared from the Rumbling's destruction. Reiner Braun and Floch were both wounded by pieces of the Walls when the Colossus Titans emerged, and there's no way they were the only victims -- meaning the first people harmed by the Rumbling are the very people Eren claims to want to protect. Not to mention the millions of Colossus Titans currently following Eren off Paradis Island who aren't exactly watching their step. Who knows how many Eldians on Paradis have already been flattened?
Eren Jaeger is also hardly a champion of Eldians, considering he only intended to save the ones on Paradis Island. Thousands of Eldians live inside the Liberio Interment Zone in Marley, and it's been implied that Eldians live sporadically all around the world. However, Eren clearly announced his intention to end "all" life beyond Paradis' shores, meaning Eldians around the rest of the world are out of luck. Killing the people he's fighting for makes it clear that he's not actually fighting for them. People like Floch are fine with any means to Eren's end, and even Jean kind of understands, but they are under the impression that Eren is doing this for them when all evidence indicates he's doing it for himself.
After beating up his best friend, berating his foster sister, betraying his brother, and manipulating his father, it's clear that no one is truly important to Eren Jaeger in his quest to destroy the world. If Eren truly wanted to protect the Eldians on Paradis Island, he wouldn't have made them the enemy of the entire world by re-igniting the war with Marley. Now, it's clear that Eren's actions at the beginning of Season 4 were just to give himself an excuse to destroy the world. The only question left is how many more of the Eldians that Eren claims to want to protect will die because of the Rumbling.
