root:~# sudo snap install hello-world
error: system does not fully support snapd: cannot mount squashfs image using
    "squashfs": mount: /tmp/sanity-mountpoint-362302586: mount failed:
    Operation not permitted.

Wo liegt das problem?

Debian: 10.7.1

Snap:

snap  2.37.4-1+deb10u3
snapd  2.37.4-1+deb10u3
series 16
debian 10
kernel 5.4.140-1-pve