This is causing many issues.
user@debian-buster-test:~$ sudo iptables --list
iptables/1.8.2 Failed to initialize nft: Protocol not supported
lsmod shows that fewer modules are load. And module auto loading is broken. This breaks Whonix firewall. Will therefore disable remounting /lib with nosuid,nodev. But no security reduction. There are no devices and no suid in /lib anyhow. And permission hardening was speed up so that parsing /lib in permission hardening is ok.
Linux Kernel Runtime Guard (LKRG) - Linux Kernel Runtime Integrity Checking and Exploit Detection - #16 by Patrick can also cause iptables/1.8.2 Failed to initialize nft: Protocol not supported