"Vechimea" as "age" applies when talking about how old a thing is. "Vechimea" can also mean "experience" when it is related to how long someone has been working in a domain, for example. "Vechimea este de zece ani" should also have "The experience is of ten years" as a correct translation. .
Why can't you say something that sounds more natural in English like "It's ten years old?" Isn't it the same?
In what proper English is it correct to say: "The age is of ten years." ?!?