Both my old Fedora 38 in the old Qubes 4.1, and Fedora 38 in Qubes 4.2 have iptables installed via the package named iptables-nft which generates nft rules using the familiar old iptables commands.
So in Qubes 4.1, Fedora 38 when I was issuing iptables commands, it was actually generating nft rules which are viewable using nft list ruleset.