How do we know that the accounts reported are being actioned by the mods and are temporary/ permanent ban based on the plagiarism reported?
I tried to check
https://bpip.org/Profile?id=3407141 but did not got any hint of ban

sometimes it takes time for them to take action. you might have checked bpip too early when the mod still hasn't made any action. after checking the bpip right now it is shown that the account is banned. also, LoyceV mentioned that some mods do not have banning privilege that's probably why even if the thread is already deleted you don't immediately see the account being banned.