On the other hand, with the Senator from Mastercard running matters, I don't expect to see any consequential changes.
If we would wait until the shareholders actually receive the money, it means they have the ability to arbitrarily decide when the revenue will be taxed, so they'll ensure that it definitely isn't taxed now. So the result would be that profits are never passed through until/unless absolutely necessary - or perhaps they can wait out a couple governments until some decades later the rules change.
Real estate (especially in Prop 13 California) would go up in value and could be borrowed against. Same with collectibles. I hear what you are saying in that the gaming on a simplification begins on Day 2.
With tax law, I'd say that the West is covering new ground in the last 100 years. Multiple mitts in the pie of legislation who all want something different (money, partial control of the taxee, veering of social goals) resulting in increasingly arcane rule sets, edge conditions resulting in tax court decisions with yet more fuzziness on the outlines.
The death of self employment and economy of scale of the modern corporation leads you to some weird places.
Real estate is a good example - assume non-appreciating real estate, which is the historically main example of a revenue generating asset (i.e. the rentier landlord class historically). If you defer taxation of profits until they're removed from the company, then any rent-earning landlord can instead of earning rent, getting taxed, and investing that after-tax money in more real estate would establish a corp for that, and use the rental profits (untaxed) to buy more real estate within that corporation. It gives a tax advantage (ability to arbitrarily defer) to everyone who can put their earnings under a corporation, and punishes those who can't.
The key problem with such taxation is essentially the same as moving to a consumption-only tax - it means that you disproportionally tax the people who (have to) spend all their income to buying things for consumption (i.e. the poor), and don't tax the people who use their income to buy revenue-generating assets and control (i.e. capitalists); it's a rich-get-richer, poor-get-poorer form of taxation.
Is poor-get-richer, rich-get-poorer the purpose of taxation? Why?
On the other hand, as others note, there are so many ways for individuals to defer taxation, for example in the case of 401 (k)s, or even eliminate it in the form of large charitable contributions or other mechanisms. So I'm not entirely opposed to some level of corporate income tax.
The thing you ascribe to capitalism is a failure not of some ideology but a problem with human nature. If you blame capitalism and throw up your hands the problem can't be addressed.
It appears to be baked into the cake of humanity.
The tendency for money and resources (and pretty women I suppose) to pool has never been well dealt with. All large-scale systems for business and government seem to devolve into dogfights over scarcity.