TS-4468, we restrict session reuse for both or hostname to match the SNI name as well as the hostname for session reuse. By default this strict matching is appropriate. The origin server may be checking that the SNI name matches the HTTP request hostname.
However, for some origins, this check is not performed. And the strict check will reduce session reuse. For a reverse proxy case, we may want to reintroduce the original lax matching for the improved performance.