I'm not quite sure what your point is. Or I know what your point is but I'm not sure how it's related to discussion of ad-based vs paid because it's true for both, ad-based as well as paid.
I think the OP's point is that when the VC money is gone, they might have to go towards adverts in some way if they struggle to monetise otherwise, so it's too early to say that they are not ad-supported