Once you produce everything for 10c locally without human labor, those unemployed human laborers won't buy your 10c thing because they are unemployed. You need more to bring back the production: bring back the employment as well.
If you're not arguing against automation then I think we need to think about what happens when we expand your timeline a little. Are there really enough 'employment' jobs that can't be automated for billions of humans of different intelligence/physical abilities?