while it is true you should not enable VT unless you really use it, there is no more risk if the feature is on or not. you need to protect your system the best you can, whether it is for virtualization or not. VT makes nothing possible that was not possible before!

Is enabling virtualization bad?

In most cases enabling virtualization is fine. In rare cases (you are a high profile person and will get targeted attacks and in particular rootkits) it’s safer to keep it off.

What happens if I turn on virtualization?

CPU Virtualization is a hardware feature found in all current AMD & Intel CPUs that allows a single processor to act as if it was multiple individual CPUs. This allows an operating system to more effectively & efficiently utilize the CPU power in the computer so that it runs faster.