Adding to the internet and hoping this will help someone.
I had a Zpool that wouldn't delete, so I asked AI for help. They ultimately did help, but it was a long process. It would have been longer if I had had to look for the answer myself.
The command that saved me was:
sudo zfs set volmode=none zroot/. This caused the OS to stop seeing the pool as a disk volume.
After issuing this command, zpool destroy worked as expected initially.