The vulnerabilities associated with early TLS (Transport Layer Security) are serious and left unaddressed put organizations at risk of being breached. In fact, it will be very difficult (borderline impossible) to pass PCI compliance if TLS version 1.0 has not been disabled.
If your site has online ordering, TLS 1.0 must be disabled. Please note that the small percentage of site visitors who use Internet Explorer 9, or older versions, will NOT be able to connect to your site at all. However, the percentage of users with those older browsers is typically less than 4% and is declining daily.
If your customer calls saying they can't connect to your site, have them upgrade their browser or better yet, have them install Google Chrome:
If you are intetested in learning more, check out https://blog.pcisecuritystandards.org/migrating-from-ssl-and-early-tls.