It doesn’t really make sense, for the same reason that corporate income tax in general doesn’t make much sense. A corporation is owned by people, when the corporation makes money, that money, one way or another, ends up in the hands of people who pay progressive tax on it. If you think that the government isn’t making enough money off of corporations, the answer is to raise capital gains taxes.
Progressive income taxes on corporations are bad policy for many of the same reasons that corporate income taxes are bad policy in the first place. Corporations are artificial constructs and they have a really easy time reorganizing to behave in artificial ways to shed tax burden. Institute a progressive corporate income tax and watch as every major corporations spontaneously transforms into hundreds of micro-corporations that own each other’s stock, and “contract” all of their responsibilities to each other without changing anything except to increase inefficiency and make internal job transfers more complex. Just tax people and be done with it, taxing corporations is taxing people, just with an added incentive for wasteful tax-avoidance.
A corporation being very large doesn’t necessarily mean that it has a monopoly. I don’t find the argument that there are significant monopolies in the high-tech industry to be persuasive.
Moreover, the competitive landscape among America’s high-tech industry is very active. Each of the major tech companies is regularly sniping at each other’s major markets. Microsoft introduced Bing to compete with Google Search and Azure to compete with AWS. Google introduced Google Cloud to compete with AWS, GSuite to compete with Microsoft’s productivity suite, and unsuccessfully introduced Google Plus to compete with Facebook. Amazon is ramping up an advertising wing to compete with Google Ads and investing in Twitch to compete with YouTube. And everybody these days seems to have a video streaming service of some sort competing with Netflix. This seems like a golden age of competition.
Breaking up a high-tech monopoly would be tough because unlike historically successful breakups it would make no sense to do geographically. But for now it doesn’t seem like anything needs to change.
Progressive income taxes on corporations are bad policy for many of the same reasons that corporate income taxes are bad policy in the first place. Corporations are artificial constructs and they have a really easy time reorganizing to behave in artificial ways to shed tax burden. Institute a progressive corporate income tax and watch as every major corporations spontaneously transforms into hundreds of micro-corporations that own each other’s stock, and “contract” all of their responsibilities to each other without changing anything except to increase inefficiency and make internal job transfers more complex. Just tax people and be done with it, taxing corporations is taxing people, just with an added incentive for wasteful tax-avoidance.