To the extent it's true that being "bad for business" is no longer enough of a disincentive for corporations, as I've already said, one key reason is that the corporations have bought regulations that favor them and disfavor potential competitors.

It's true that that's not the only factor involved. Corporate governance is broken. A big part of that is also government regulation, which does to some extent prevent outright fraud (for example, the S&L debacle in the 1980s), but is perfectly fine with other practices, like golden parachutes for executives and corporate takeovers in which the buyer gets the assets but offloads the liabilities on the taxpayers, that do just as much damage, if not more. All of these things are regulated--but the regulations don't stop harm from being done.

There is one other factor that works against corporate governance which is not, in itself, a product of government regulation: the fact that most share ownership now is not individual stockholders but mutual funds. That means most people don't even know what corporations they own even small pieces of. But mutual funds are a big advantage for most people investing for their retirement, because they're an obvious hedge against risk, so they would exist even in a true free market without any government regulation. The problem is that, as far as the individual corporations are concerned, their time horizon is now much shorter. The mutual fund has to care about providing returns over a long time horizon, because it's holding people's retirement accounts, which might not be drawn on for decades. But the corporations only see short term trades being made, many of them by those same mutual funds, trying to increase their returns. So corporations have to focus much more on short term returns instead of long term planning.

That would be one area where a government ought to be able to improve things, because a government's time horizon ought to be long-term. But it isn't. Government's time horizon is the next election. So even in this area, governments are actually worse than corporations.

The massive power that corporations have, as compared to individuals, is itself a product of the fact that our society has evolved now for well over a century to have government regulations that are bought by corporations to favor them. So you are correct that we can't just instantly scrap every government regulation, but not change anything else.

That does not mean that the regulations, on net, are doing more good than harm. It just means we've gotten ourselves into a very deep hole, which we can't climb out of in a short time. But at the very least we could try to stop digging.

The Chicago meat packing industry, for example, did much the same kind of bullying of their supply chains that Amazon and Walmart are now infamous for. And governments that were supposed to be preventing that sort of thing (since much of it was illegal even then--the tactics are basically the same ones organized crime has used for centuries, after all) did absolutely nothing to stop it. The Federal government finally stepping in and passing laws and regulations was not a case of government reining in a free market; it was a case of a bigger government stomping on a smaller government.

It did improve things, at least for a time, but what's the condition of the Chicago meat packing industry now? Or for that matter our food supply chain in general in the US, which has been regulated up one side and down the other for more than a century? We have beef full of antibiotics, vegetables full of pesticides, ethanol from corn in our gasoline while other food crops can't be grown profitably because the government doesn't subsidize them the same way, and a massive epidemic of obesity. So how is government regulation helping, exactly?