oh what an interesting question! i think it was just the overall obscurity of it
i found it around 2015 probably on touhouwiki or something, and just the fact of it being related to touhou but a different thing was interesting. i also found the soundtracks around then, really loved them. took a while to get the games to run but i enjoyed them
and ofc when i started my youtube channel and online presence overall in 2018-2020, i wanted to just bring more attention to it and it ended up with me getting an LNB and a score record so yeah, it will always be an iconic series