So, for better or worse, we are a long long way from a Government that only intervenes when there's a monopoly.
We are where we want to be. The poster asked the question of should government intervene. To say that "government will intervene whether we want to or not" is to engage in circular reasoning. One supposes that in order to ask the question, there must be a choice for the answerer to make.
I also have heard this "those were the old times" argument quite a bit lately, and its wearing thin for me. To some degree, yes, government has intervened and mucked around with markets. But to a larger degree it hasn't. And the decision to muck around or not, last I checked, was a political one, not done simply because times have changed. It's very much debatable whether government intervention in various markets constitute a good or bad thing.
Teddy was a smart man. So was Jefferson. We continue to find and address these issues as we can, doing the best with what light we have.
My issue with your line of reasoning is that it's academic. You're making an argument based on a model of Monopoly = Government Intervention and that's not where we are anymore.
There's also a case to be made, which is made by every monopoly, that having a single player actually advances things in the public interest. In other words, by having Apple control so much, the future of smartphones in general is actually advanced much farther than if they didn't. I don't buy this argument as a general rule, but parts of it do seem to make sense. After all, getting 40 individual players to agree on a standard is a lot harder than getting one company to do so.
Perhaps the natural state of the technology industry is to slowly swing between monopolies and openness. During times of monopolies, de facto standards get adopted and interfaces stabilized. During times of openness, innovation rules and paradigm changes are made.
I'm not saying this is a good thing, just that it looks like a pattern might be setting up.