Aoba is referring to the public contest held by Kyoto Animation which required participants to send in draft novels, with the winners getting promised that their stories would be turned into anime. This contest was held before the attack.

However, the allegations of plagiarism and the plea made by the defense were denied by Kyoto Animation.

They further argued that Aoba believed a female director at Kyoto Animation, who he had admired, had stolen the novels he submitted. Her success compounded by his own failures fueled a hatred in him, which also played a part in Aoba’s crime.

Man, this is why many studios stop running these kind of competition and won't accept unsolicited submissions. People would claim the company stole their ideas even if it's developed independently.

I think the only question now is when he'll be hanged. I don't agree with the death penalty, personally, but that's not my call to make. He's totally screwed.

Where there any doubts that he wasn't the murderer..?

Reposting from my misskey:

In view of the Kyoani case progressing, I want to talk about Dr Ueda Takahiro, the doctor who was in charge of the skin grafting of arsonist Aoba Shinji.

Not a single piece of Western media has named Dr Ueda for his work in advancing skin grafting, and in particular, the technique called Cultured Epithelial Autografts (CEA), which I think is what was used for Aoba.

For starters, this is Dr Ueda's Researchgate and Researchmap profiles with his papers. At this point there doesn't seem to be a specific case report talking about Aoba's medical progress, but it can be inferred that he may have been included in studies that included multiple patients. I also don't have access to the Japanese-only research papers (and my Japanese ability isn't at an academic level) and only what was originally published in English, but for an idea of what the skin grafting procedure entailed, you can read one of his older English-first publications that are available online (this predates Aoba so the technique is likely even more refined now). I'm sure much of what has been learned has also been incorporated into the Japanese Society for Burn Injuries (JSBI) Clinical Practice Guidelines for Management of Burn Care (3rd Edition), which Dr Ueda contributed to.

What did Aoba's skin grafting process entail? English news sources didn't talk about it, but Mainichi did in this article (my interpretation):

Aoba had 90% body surface area of 3rd degree burns. It seems that at the time of the arson, he was wearing a fanny pack around his waist, which kept some skin from being too injured. Part of that intact skin was taken for cultures and placed on top of an artificial dermis, for a duration of 4 weeks. He underwent 9 surgeries for the burns (likely including the original debridement and graft harvesting procedures).

Asahi Shinbun has an article on Dr Ueda's reflections about the incident in English.

You can also find some of his own thoughts and retweets about the case on his Twitter/X