We've had tons of issues with disabling older TLS versions. Including breaking clients as well as incoming mail server connections that dont support higher TLS versions, which then turns into support tickets of users complaining they are not receiving x email.

We also considered disabling tls <1.2 but after some analysis there is still too much clients and even servers that aren't tls 1.2 enabled... It's a bit too early to disable the support for it.

Appreciate the feedback!