This is really great news. I imagine some people have tried for many
   years to make this happen.
> * ssh(1), sshd(8): use the hybrid Streamlined NTRU Prime + x25519 key
>   exchange method by default ("[1]sntrup761x25519-sha512@openssh.com").
>   The NTRU algorithm is believed to resist attacks enabled by future
>   quantum computers and is paired with the X25519 ECDH key exchange
>   (the previous default) as a backstop against any weaknesses in
>   NTRU Prime that may be discovered in the future. The combination
>   ensures that the hybrid exchange offers at least as good security
>   as the status quo.

   This  a good time to learn to configure accepted algorithms in one's
   ssh daemons and clients. I think an old trick an attacker could perform
   was to mutate the handshake so as to reject high strength protocols.
   The client would then silently try lower strength ones, without warning
   the user.
   The various options are shown in `man ssh_config` for clients and `man
   sshd_config` for servers.

References

   1. mailto:sntrup761x25519-sha512@openssh.com