I am not an expert on Notch's slide into craziness, but I'd argue that the episode you mention it might not be the start. His start was as a "anti-SJW" game dev

I am not an expert on Notch's slide into craziness, but I'd argue that the episode you mention it might not be the start. His start was as a "anti-SJW" game developer which got him hated and vilified by his former fans. I'm not saying these people were rays of sunshine before, I'm saying they could be talked to without them foaming at the mouth and you face palming at how unhinged they were. I was using the meaning of benign attached to tumors.