Why wouldn't the SIGKILL kill a zombie?

I know that a zombie cannot be killed with SIGKILL to it (not to the zombie's PPID). So, with a risk of getting downvoted, let me ask these genuine doubts that I have:

If a zombie process can be 'reaped' by the parent process, and if the zombie process is only an entry in the process table and all it remains is to remove that entry from the process table (as many of the resources say), and if SIGKILL can kill any processes and release ALL the resources used by the process with no consideration of it being a parent or child then why wouldn't the SIGKILL do the seemingly trivial job of removing this entry from the process table. If the purpose of this entry in the process table is to give a chance to the parent process to read the child's exit status, why would the SIGKILL even consider it given that SIGKILL is known to be very very ruthless.

That said, I definitely know there must be a reason why SIGKILL won't kill the zombie, so please enlighten me with what I am missing.