remote ssh login fail "Authenticator provider $SSH_SK_PROVIDER did not resolve" (macOS)

I for the first time am attempting to log in using an external (public)
network from my M1 (Apple) machine to my remote openbsd machine/server.

The ssh connection is usually successful using public key
authentication.
I can also still log in using my Android termux app, hence the problem
seems to come from Apple's OS ssh implementation ?

(from the Apple terminal)
> ssh -vvv sylvain@saboua.xyz
OpenSSH_9.8p1, LibreSSL 3.3.6
debug1: Reading configuration data /etc/ssh/ssh_config
debug1: /etc/ssh/ssh_config line 21: include /etc/ssh/ssh_config.d/*
matched no files
debug1: /etc/ssh/ssh_config line 55: Applying options for saboua.xyz
debug3: expanded UserKnownHostsFile '~/.ssh/known_hosts' ->
'/Users/sylvansab/.ssh/known_hosts'
debug3: expanded UserKnownHostsFile '~/.ssh/known_hosts2' ->
'/Users/sylvansab/.ssh/known_hosts2'
debug1: Authenticator provider $SSH_SK_PROVIDER did not resolve;
disabling
debug3: channel_clear_timeouts: clearing
debug1: Connecting to saboua.xyz port 22.
ssh: connect to host saboua.xyz port 22: Operation timed out
>

(only addition made to /etc/ssh/ssh_config on M1 machine)
Host saboua.xyz
User sylvain
PasswordAuthentication no
PubkeyAuthentication yes

(relevant /etc/ssh/sshd_config excerpts from obsd srv)
Match User sylvain
PasswordAuthentication no
PubkeyAuthentication yes
AuthenticationMethods publickey

--
Sylvain Saboua