Comparing firewall syntax for SSH (port 22) with default-deny:
#iptables (Linux)
iptables -A INPUT -p tcp --dport 22 -j ACCEPT
iptables -P INPUT DROP
#nftables (Linux)
nft add rule inet my_filter in...
The only one of those I know how to read is iptables. And if what you are specifying is your complete firewall configuration, it would definitely not work.
There are a number of packets being dropped, which you would still need in order for things to work correctly:
Communication with localhost
Replies to your own outgoing connections
ICMP messages related to the allowed connections
There are a number of packets being dropped, which you would still need in order for things to work correctly:
Communication with localhost
Replies to your own outgoing connections
ICMP messages related to the allowed connections