It wasn't, then or in the 1860s, hence the strong, modern, adaptive federalism we have today that treats states as provinces and makes important things move quickly.
One could squint and say states matter today, but that's just admitting a need for glasses. They are ghosts of what they were, and increasingly need to be retired.
It will be nice when we put to pasture the policy-as-experiments across states for things that are clearly universally demanded: finance, health insurance, women's medical care, education, defense, gun control, decreased corporate control of the food supply, transportation, environmental regulation, and so forth. It's amazing how much the modern GOP has pushed folks towards this, may they continue their business Republican-led shenanigans to unite the country and encourage progress when otherwise we would be slovenly.
Why is this the case? Duplication of fixed costs are expensive.
Let's get rid of these crufty overindulgent home-owners-associations-on-steriods and federalize already.
(paragraphs 1, 4 serious, the rest in jest)