Coauthor here-- thanks for the kind words. NJW retired right before he started this project, in Feb 2021. On his WildEgg channel he said he was doing a series

Coauthor here-- thanks for the kind words. NJW retired right before he started this project, in Feb 2021. On his WildEgg channel he said he was doing a series where he'd teach amateurs how to do math research, behind the members paywall. For the first problem, he said he'd solve the general polynomial. I thought it was a joke, because everybody 'knows' that we can't go beyond degree four. But no, 41 videos later, he had done it. Two years after that he still hadn't written it up, so I wrote a draft and sent it to him, which evolved into this paper.