I still come across clients with the older version of EV , there are many reason to upgrade to the latest version such as new features , official support from veritas ,Product enhancement but out of all these you first need to think about security and the reason why is

TLS 1.0 and 1.1 are already deprecated and if you still using it , you must need to aware about security risk which you have right now in your business critical environment . from Enterprise vault 12.4.1 , TLS 1.2 is flawlessly supported. so if you running lower version have you plan ready to upgrade !!.

https://www.veritas.com/support/en_US/article.100038087#12.0.x?q=*&undefined&docRepo=true