A lot of 'support' for FF comes from fans of acts who did not chart in the Billboard and are jealous about their success, so they pretend to support FF, a nugu group from a tiny company, to shade these acts.
The whole thing is not too different from the days of GFriend when it beat Lovelyz (then an SM act), got past Red Velvet and competed for supremacy against Twice. and briefly won for some time.
A lot of people supported GFriend, but about 2/3 of such support was gone when BlackPink debuted and IOI got most of GF's thunder, and when its heyday ended, only a few buddies remembered it.
FF has one hit song, and again I will have to compare its record with that of Lorde, who spent 9 weeks at #1 in Billboard Hot 100, and Billie Eilish, who actually beat BTS for the title for highest selling album of the world, 2019.
At the height of her power, Lorde only could manage a semi-arena tour. Her venue at Los Angeles was the Greek Theater in Griffith park, about 6,000 ; New York, United Palace ( 2 days), capacity 3,500 and 7,000 total. She only managed to do an arena tour in her native New Zealand, 12,000 in Spark Arena at Auckland. Since her popularity has mostly faded by now she now does auditorium tours for one single days.
Billie Eilish was made a celebrity , but she does arena tours now. She did go to the Gochuck in Seoul, for one day, courtesy of Hyndai Credit Card last year but a more famous local singer was doing a 2 day concert in the Olympic Stadium a month later so Billie's thunder was stolen by the then 1,343 years old singer.
Of all female acts coming from K-O-R-E-A, Twice and BlackPink did stadium tours in USA or Europe.
Kara and SNSD had tours at Tokyo Dome, plus the two above.
The 1,343 years did a two day stadium concert in K-O-R-E-A , the first by any female act there.
Given that FF's song is more popular than FF themselves, I think at most they will be lucky to do auditorium tours like Lorde. Which means some income but no jackpot for the owner who has become too lazy.