A tangential question, why is .so the new cool TLD to use for tech startups/projects? I know the lack of availability of .com/other common TLDs is a problem. I

A tangential question, why is .so the new cool TLD to use for tech startups/projects? I know the lack of availability of .com/other common TLDs is a problem. I understand the reasoning behind using .io to represent software/saas startups (stands for inputs/outputs). I don't understand .so though. From what I remember, Notion was probably the first high profile startup using it, and it just kinda took off. Searching "why .so domain" comes up with nothing except a Reddit thread with the Notion founder saying it was mostly because it was just an available TLD for "notion" at the time.