I’d say no, based on a few factors.

First, any plant matter that gets into the water is heated. Second, it will only get in there after the water has had smoke go through it, warning the liquid above ambient.

Third, since the steeping would occur with adulterants, is it really a tea/tisane at all? Typically, anything other than prepared plant matter being added during a cold brew is going to interfere with steeping, so having the ash, tars, and residual resins/terpenes/etc in the water beforehand seems less like a tea and more like a stock.

And, yeah, you can argue that a stock isn’t super dissimilar from a tea, but you can’t cold brew a stock. Too many of the things in there won’t get into suspension, or dissolve without heat. Even in vegetable stock.

Fourth, unless you’re broke, you aren’t going to be smoking much leaf, there’s supposed to be mostly bud in there. While you can make a tea from flowers, tea tea isn’t predominantly flower of the camellia.

So, as a shower thought, this is fucking awesome. It just doesn’t hold up to scrutiny.