To me it is pretty ridiculous how much labor is taxed, and how little capital is taxed. Especially if we are worried about automation and lack of productivity growth, it seems so counter-intuitive that we are completely stuck to a tax system that devalues workers.
The reason is simple: labor has less options. Capital can mostly go where it pleases - if it is taxed too much it might flee the country. But your 160 million workers aren't going to uproot themselves and move to another country because they're too heavily taxed.
Historically this was not the case at all. It's only during the modern neoliberal era that this is true.
Thing to remember Capital isn't a primary resource like energy, infrastructure, materials, and labor.