This is a compatibility vs. security trade-off.
Certbot chose to use defaults taken from
As you can see, there are “modern”, “intermediate”, and “old” configurations (which choose different points along the security and browser compatibility trade-off—“modern” is most secure and least compatible, while “old” is least secure and most compatible).
The default that we chose based on Mozilla’s recommendations does not comply with the PCI requirements because it allows the obsolete TLSv1 protocol (which some old browsers still require). You can configure this in
/etc/letsencrypt/options-ssl-apache.conf, where you could choose to add
-TLSv1 to the end of the
SSLProtocol line (to comply with the PCI requirement) or
-TLSv1 -TLSv1.1 to comply with Mozilla’s “modern” recommending in this specific regard.
Maybe we should ask Mozilla if they want to revisit this issue in their recommendations in light of subsequent developments and the passage of time.