Source et explications : https://www.redhat.com/en/blog/rootless-podman-nfs

Changer

~/.config/containers/storage.conf

[storage]  
driver = "overlay"  
runroot = "/run/user/1000"  
graphroot = "/home/myuser/.local/share/containers/storage"

En

[storage]  
driver = "overlay"  
runroot = "/run/user/1000"  
graphroot = "/var/tmp/myuser/containers/storage

Ou créer un FS

truncate -s 10g /home/myuser/xfs.img  
mkfs.xfs -m reflink=1 /home/myuser/xfs.img
mount /home/myuser/xfs.img /home/myuser/.local/share/containers