The article doesn't propose "optimizing" for users with some form of limitation (connectivity, device, personal disability). It proposes not excluding them by

The article doesn't propose "optimizing" for users with some form of limitation (connectivity, device, personal disability). It proposes not excluding them by optimizing only for the maximal case. Your point about hand coding progressive enhancement is well taken. What we need are tooling and frameworks that make such an approach feasible. The author laments that the frameworks du jour tend to start with (and incentivize building) the resource-heavy, complex, fragile version of a site / app.