Because we've increased our wealth consumption whilst lowering our wealth production. Doesn't matter how much you make money zip around the economy if the underlying balance of consumption versus production isn't there. Doesn't matter how attractive you make investing if you make the smartest investments outside of the USA. By dropping our protective tariffs whilst keeping our expensive environmental, human rights, and safety regulations, we've guaranteed that even though we can make American companies profitable (by lowering capital gains taxes and offering lots of corporate tax breaks), our good-paying jobs will increasingly vanish to cheaper labor markets. Anything that CAN be outsourced, WILL be outsourced. That includes CEOs; while the American company initially profits greatly from the cheaper non-American labor, within a decade or two the foreign manufacturer is the one who understands how to push the technology and eventually pushes the now-bloated American company out of that market, if not into bankruptcy.
Which completely dances around the central issue- It's American companies paying $2/hr elsewhere vs $20/hr here, and American companies taking the difference as profit, which is reflected in their disbursement of dividends and the capital gains of their stocks. It's not really foreign companies at all, or foreign money financing them. It's American companies & American investment. It won't be foreign companies leading the charge down the road, but the foreign subsidiaries of American companies.
What's happened is that the electorate hasn't insisted on fair compensation for job loss & opportunity loss from corporate entities & their owners. Lowering tax rates on investment income doesn't do that at all, and accelerates the hollowing out process we both see.
An idea that's intrigued me involves eliminating corporate taxes altogether and taxing investment income at the same progressive rates as earned income. The flimflam of offshoring corporate headquarters would disappear, and the practice of holding profits offshore wouldn't stand up to shareholder demands for what's rightfully theirs, dividends, or what's rightfully the govt's, taxes. In many instances, the advantage of offshoring isn't in labor costs, but in corporate tax advantages.
We could use the increased revenue to create systems that currently disadvantage enterprise in this country, like healthcare, and the sort of selective subsidies that other govts use to their competitive advantage. Hell, we'd probably see foreign companies moving their headquarters to this country, bring jobs and the purchase of all the stuff it takes to run a company along with it.
Such a thing would have to involve both changes simultaneously, for sure, not the usual cut taxes first & talk about revenue loss later...