That still feels like an incredible reach, since local economies nonetheless predominantly rely on the local proletariat, which necessitates the existence of said proletariat. You can’t exactly import every single little commodity or service.
Plus wealth isn’t the measure of being a proletarian anyway, but ones control over the means of production. Even if every worker in the US was a millionaire, they still would not control any aspect of the system and be entirely at the mercy of the capital owning class.