We need at least a roadmap to do this.
"And as of August 2018, the final version of TLS 1.3 is now published (RFC 8446). Companies such as Cloudflare are already making TLS 1.3 available to their customers. ... In short, the major benefits of TLS 1.3 vs that of TLS 1.2 is faster speeds and improved security."
We need to check if anything speaks against activating TLS 1.3 for all customers (are corresponding libraries marked as stable?)
Jens will bring this into grooming to discover if this is a mere configuration change or more complex.