As stated in The Will of Jyothish, Vyavahaarika Sathya is where we are.
Now, since Vyavahaarika Sathya exists, the rules that apply to it should also be meaningful. That is, unlike Adi Shankara who thought this had to be as per the Shashtras that existed at the time, I think it has to take care of the needs of all people with a will.