Well, that's my point, they aren't a monopoly in large part because "unfair trade practices" are illegal. I think they could wipe other brands out if that were not the case. They really get worried when their market share goes past 65%, seriously, it's an issue when it happens.
Yeah, and I'm sure that when the market share gets up there, they're more worried about regulation than market competition. I get that it's a thing.
That said, it keeps being said that unbridled capitalism will lead to monopoly as if it is a foregone conclusion. And also that it's bad if it does.
My view is that the first statement is unproven (that capitalism in a truly free market leads to monopoly). And that the second statement is specifically what disproves the first--if a company tries to exploit its monopoly to the detriment of consumers, that is the way that competitors develop the niche to break the monopoly.
If P&G were to obtain a monopoly in laundry soap, and were harming customers by doing so, new entrants would attempt to unseat them. Yes, they could buy up new entrants or engage in predatory pricing to destroy them, but then they're just going to spend a ton of time lopping the heads off every snake that pops up.
And even beyond that, P&G might obtain that monopoly, but P&G can't be a monopoly in everything, right? What if Amazon decides "hey, P&G is making an absolute killing in laundry soap because there's no competition; it's time for us to enter that market"? P&G may be a gigantic company, but you can't just wipe out other gigantic companies if they go all-in to beat you.
The free market is dynamic. Per this thread, someone upthread said that "generational wealth" isn't truly a thing because it always gets diluted over a few generations due to various factors. I argue the same is true in the free market. It's dynamic. There are winners and losers, but you can only remain a winner if you are satisfying customers. If you stop that, it doesn't matter if you're P&G, or Ford, or Amazon, Apple, or Facebook. You stop satisfying customers, and they WILL seek out alternatives.