I provided a piece of anecdotal evidence which, for some reason, you're doubting the veracity of. There are some who function at a very high cognitve level while being a consistent pot user, and there are some who don't. You seem to hold a simplistic view against all of those who do use pot. If you apply a one-size-fits all perspective to all pot smokers, then in your words, own it.
As an aside, losing touch with someone does not preclude further learning of that person through mutual friends. So "is" is, in fact, the appropriate word. Keep believing your crusade is infallible.