TLS 1.3 should be added in Domino 11.
There are already recommendations to disable TLS 1.0 and I have seen customers who already disabled TLS 1.0 on their SMTP servers. On the other side there are still unpatched environments which do not support TLS 1.2 today.
In a year from now there are much more servers only supporting current ciphers and TLS 1.2.
Now that TLS 1.3 is finalized and published it makes sense to look into it.
Here is a good write-up about the benefits and some details. It also contains a list of software which already supports TLS 1.3.
Daniel Nashed [ https://blog.nashcom.de ]