Well this is my opinion but despite all the hype, attack on titan is not the greatest anime to exist. The show is good, but it's not that good for it's fans to act all toxic and get defensive about it. There are better shows out there that do what AOT attempts to do, but do it way more effectively.

The plot twists and shocking moments were cool in the beginning, but later it's just for the plot and make no sense whatsoever. The story is dragged out and a lot of moments people consider "cool" are actually edgy and cringe. The pacing’s all over the place and the characters don't have any depth at all .... some characters like historia and mikasa just exist for the plot and serve no other purpose.

The world building is also non existent and only what's needed is shown. Other anime, like FMAB, Steins;Gate, CG, 86, or Hunter x Hunter (just to name a few), have set a higher bar for what storytelling and character development really mean. The focus isn’t just on shock value or dramatic deaths, it’s on building a world and characters that feel real and evolved.

Another issue is with AOT fans claiming that the ending is good or lmao a "masterpiece."
I get that the hype was real, emotions were high and this was probably something you wanted to continue loving but lying to yourself and others just isn't it. Just accept that it has a poor ending and move on.

Also the ending randomly introduced time travel, eren killing his mom, genocide and a whole lot of other bullshit If you’re still clinging to AOT as the "best" anime, maybe it’s time to realize there are others that deserve that title more. AOT’s time in the spotlight has passed, and there are a lot more anime that is a lot better than AOT.

Again I'm not telling that the anime is trash or anything, it's still better than a lot of random seasonal isekai trash, but it's not the peak it's fans claim it to be. It has it's flaws like any other anime.