>>10093144They are surviving, but that's not the kind of success that would make a competitor go "yeah, I think I want to get a slice of that pie". Cover might or might not be planning a holoKR branch, but if they are it's definitely not because of nijiKR's performance.
Also personally I'm not sure if Koreans would go for other Korean vtubers. HoloCN has similar issues back when they were still active where the Chinese fans would rather watch holoJP than holoCN.