As far as I can see, there's no way to tell how many people contribute to these statistics or how often the songs are sung. I wouldn't be surprised if some of the Holos not known for singing have only couple of dozen karaoke requests. On the other hand:
-Suisei's Bibideba is 91st (down from 68th) in the most popular karaoke songs of October: (
https://www.joysound.com/web/karaoke/ranking/all/monthly)
-Suisei's Moonlight is 29th and ReGLOSS's Feeling Gradation is 79th in the rolling monthly hot new songs chart (ie. 4th of October to 3rd of November):
https://www.joysound.com/web/s/hot-new-song/1month0kisei fans at karaoke:
-The average person singing 0kisei songs is a man in his 20s or 30s to the surprise of absolutely no one
-While the other four have at most 20% of their karaoke visiting fans be women, Suisei has an almost balanced 44%
-When it comes to female fans, over half of them are under 40 in every case
-Only Sora manages to have over 25% of her fans be over 40, Suisei is the only one to have any fans over 60 singing her songs
-Teenagers are even more scarce, with Suisei and Miko having the most
-Interestingly, Suisei is also the only Holo to have a description on her profile page (copied from Wikipedia)
