The product is permissionless final settlement, but settlement is rationed by consumer verification cost — the limit is validation cost. A base layer can only fit so many transactions per block while keeping self-verification cheap enough that ordinary people actually run nodes. Push blocksize up and you raise verification cost and centralize authority. So when demand exceeds capacity, the network rations by price — a fee market — rather than expanding capacity. And as block rewards fade, the security budget is bought primarily through fees: rising real demand funds security while simultaneously pricing marginal users off the base layer and forcing substitution onto a second chain.