What would happen if we had aggressive progressively scaled corporate taxes based on some mix of employee count, revenue, or other measures of size? As a thought experiment (disregarding international complications, measuring problems, etc, for now), how many of the worst effects of capitalism are mitigated if every company has several direct competitors?

With enough participants in the market, you might have enough potential defectors to keep oligopolistic collusion down. Employees get better treatment because they have options. BATNA.

Inspired by stuff like https://slate.com/business/2018/01/a-new-theory-for-why-amer... - the recipe to extracting maximum profit is to pay as little as you can get away with while demanding as much as you can get away with and charge as much as you can get away with. Our current tooling is fairly bad at limiting that "what you can get away with" for corporations. So what pressures would change it?

Currently we tilt the playing field in favor of larger corporations, in addition to the natural inclination in many areas of economies of scale, with stuff like forced arbitration being allowed. "Should Amazon be broken up?" is just a small part of the "how do we make sure economic power is well-distributed instead of concentrated?"

Or do we think systems with too-big-to-fail players are a good thing?