> Assuming the network doesn't produce external value to the people transacting on it (for example, lower transaction fees than alternatives, lower cost to enforce contracts, lower spread trading equities or currencies etc).

The hypothetical value generated accrues to those who hold equity in the miners or network operators (stakers in a PoS system) - not the tokens themselves. If Starbucks pre-sold coffee as tokens, the fact that Starbucks is selling more or less coffee means nothing for the value of the token.