First of all thank you for writing a detailed answer. Clearly you have taken a lot of efforts and been very articulate.

> Your position ignores the fact that being the 1T gorilla in the room gives them significant advantages that, to them, are worth the disadvantage of slower innovation.

You are absolutely right. You are talking about regulatory capture here and larger companies are in better position for regulatory capture. What you are proposing however is more regulation to prevent this very situation. Very likely this will lead to even more regulatory capture. We have seen this with health insurance, utilities and telecom companies where government steps in to prevent these companies from making too much of profit but then grants them monopolies causing stagnation of innovation.
The correct solution IMO here is that less power in the hands of government so there are less avenues for regulatory capture.

But let us look at the facts. Is Apple, Google or Facebook today too large because of regulatory capture or innovation? Compared to any industry I think tech in USA is growing due to the latter. (Exceptions like Visa, Mastercard, Intuit exist, and I do believe government has failed to be a custodian of markets here).

> Your argument is kind of like the high school physics problem of "let's ignore friction and wind resistance" except worse because to me it's more akin to arguing for Aristotle's bodies of motion when you already have a lot of experimental evidence showing the model is incomplete/wrong.

Fair enough. After all, all theory must be put to test. We can easily see my logic in practice by taking example of utility companies like PE&E, Oil and Gas industry, health insurance industry or almost every industry in Europe which is heavily regulated to prevent them from making "too much profit" or is restricted in terms of how much they can grow. Contrast nearly any industry on planet earth today with USA's tech industry and USA's tech industry comes on top in terms of wealth creation, better workplace standards, innovation and in some cases mind boggling ambitious companies like SpaceX. Not only American tech companies are engines of growth and some of the best places to work for, they are also cheap for their consumers and massive force for good at global scale. (This is not to say they don't have any dark side but when you put all numbers together they come up on top.)

What is not broken should not be fixed.

> * Big tech is acquiring companies before they can compete. This both hurts innovation & the US economy in the long term because these big tech companies are extremely efficient at their own growth, but that's not necessarily yielding the broader benefits needed by the economy for productivity/innovation

Yes, that is a good principle that these people can talk about rather than "too big" argument. Once these principles are clear, I think it is much easier to show them as well known economic fallacies.

> I think "too big" or "too much power" is used as short-hand for these

Yes, and that is precisely what I find dangerous. We must be debating those very principles and not the question of whether we need more regulation or not.

For example on this very HN thread hoe many people are debating those precise principles ? Almost none.