Anime production is a very hard job. It takes countless hours of planning an anime scene to animate it and on top of that, Anime studios often get criticized for a little bit of a mistake.
It is a well known fact that Mappa studio was under a lot of criticism for Attack on Titan season 4. The creator of the Attack on Titan series recently made sure to let the fans know that it some scenes will be difficult to animate for Attack on Titan. He even apologized to Mappa for that.
On October 13, a new trailer was released for Attack on Titan final season part 2. Hajime Isayama also commented at this moment:
I am really looking forward to the start of final season part 2. Even in the original, it was really difficult drawing, and I am very sorry that Mappa will have a hard time again for many scenes, but I am sorry.
But the difficult scenes are the most that I am looking forward to. I hope that the people who see it for the first time in anime will also enjoy it
Attack on Titan final season part 2 will be released on January 9th, 2021. You can watch the trailer below: