This would explain how supermassive black holes in center of galaxies came to be (by merging). And those SBH were may be created by hypernovae explosions of population 3 stars.
PS: Interesting perspectives and related: youtube.com/@bgaede
Astronomers have detected, for the first time, three supermassive black holes located in the same galaxy. However, while this discovery is significant, further studies will be needed, particularly to determine their fate.