I don't see how taxing people indefinitely so that an indefinite amount can be spent to maximize employment through delivering something which can be delivered

I don't see how taxing people indefinitely so that an indefinite amount can be spent to maximize employment through delivering something which can be delivered cheaper and better with more technology is optimizing human wellbeing. If the government is spending money on delivering X, they should do it as cost-effectively as possible, and the rest of the money can then be spent on other things or can remain in taxpayers pockets so they can spend it elsewhere. If the government is going to try to achieve full employment with everything it does, it will just be a disaster.