Do we know that worship/knowledge is tied to power level in the DV? I know in the Iron Druid Cornicles that it is implicitly stated several times. But in the DV all that I recall is that if you are forgotten from the minds you cease to exist.
Kinda? As far as I know we've never had any direct confirmation of a
Power Increase, but we do know that NeverNever Entities require a tether to mortal consciousness, such that if they are forgotten completely they cannot interact with reality any more and are said to be "consigned to Oblivion" (though there is debate what all that means). That being said in Day One it was confirmed that enough Belief
can create new beings, though it also says that more often an existing being will alter itself to fit the new myth/shape and piggy-back it.
My read of it, particularly the couple times Bob has touched on it, is that the Belief affects the Connection to the Mortal Word, which in turn limits how much of their Power they can Leverage. It wont in itself Create Power from nothing, though it could gather up old/lost power that resonates enough which would more or less look like the same thing (Conservation of Energy notwithstanding). More often it would attract a Powerful Being to what is essentially an unused and unclaimed Tether.
