I don't think people realize how the "aot is problematic" thing is meant and immediately jump to the conclusion that it's not true because obviously the Marley are painted as the bad guys and their treatment of eldians is shown as wrong so there's no problem right?
The real problem is how the whole eldians are jews metaphor is executed. I'm not saying that it was Isayamas intention to do so (I'm also not saying it wasn't) but the metaphor seems like it was written by someone who believes in antisemetic conspiracies.
I want to preface and say that I don't necessarily want to accuse Isayama of intentionally making snk antisemitic but I do believe he drew ideas from some harmful conspiracies, maybe even without considering that it might not be a good idea. There's still the possibility but I'll give him the benefit of the doubt
First of all what is the metaphor,
Eldians are a race of people who are said to have commited countless atrocities in the past against everyone in the world and who ruled over everything with an iron fist.
That sounds like antisemites describing the "jewish elite". A slogan very prominent in nazi propaganda, They said jews were secretly trying to take control over germany and had already done so in other countries like england and the US. The nazis said that they wanted to "save" the german people from the "evil" jews who were trying to take them over. Throughout history jews have been blamed for almost everything that went wrong, from famines to the plague, most of the time jews were the first people blamed if anything goes wrong.
So these groups have something in common, they're both blamed for a lot of atrocities commited and evils that happend in the past. The difference is, the eldians did actually commit these evil things. They did actually kill millions of people and cause chaos everywhere and ruled over everything.
Then there's the lizard people thing. Now there's no actual lizard people in snk but there's the Tyburs, a family of rich eldians (who are apparently meant to be a metaphor for jews) who secretly rule over Marley and don't do anything about the suffering of their own people.
The first part reads like a lizard people conspiracy. The jist of every lizard people theory is that a secretive group of people runs all the governements and banks. They do this from the shadows and have done so for ages. That exactly is the crap jewish peopel are accused of and that is exactly the thing the Tyburs are.
Ymir Fritz and the eldians all being decendents of her and her subjects also reaks like a comparison to how the jews are decendents of Abraham and "gods chosen people".
So overall, the eldians in attack on titan are accused of having commited countless crimes in the past, even some that jews have been accused of too. They are controling the governement from the shadows and are something like "gods chosen people". How is that not a really bad metaphor for jews.
Like I even left out the most important thing whcih is that they are literally forced into ghettos, treated as subhuman and made to wear armbands to identify themselves.
Now like I already said, the problem is that the eldians actualy did do these evil things the jews were accused of doing irl.
There's even a story in aot which shows that. Ksaver tells Zeke that there once was a plague that killed millions of people but not a single eldian because the founding titan at that time used it's power to rewrite the dna of the eldians so they couldn't catch the virus. That's what, acording to antisemetic people during that time, happened to the jews during the plague. Jews tended to get the plagues less often, there's a few reason for that that are all explainable but none of them are witchcraft which is what the founding titan did to prevent eldians from becoming sick and also what the jews were accused of doing.
If just think you shouldn't consume attack on titan uncritically without acknowledging how incredibly harmfull the eldians being a jewish metaphor is.