The problem is the type of business he is in tends to foster natural monopoly, if left unchecked. The same was true, by the way, of Wal-Mart. Amazon musculing in on department stores isn't one company out-competing another. It's one industry replacing another. Okay. Nothing wrong with that. The fax machine is going out of date, too. But what is the nature of within-industry competition? What is Amazon doing within the online retailing space? They are engaging in anti-competitive behavior. That's the problem. Then you have to ask what the solution is. You either break it up, or regulate it as a monopoly.
https://www.thenation.com/article/amazon-doesnt-just-want-to-dominate-the-market-it-wants-to-become-the-market/
Yes and no. The thing about retail is that it has a remarkably low barrier to entry, and not much about it is copywrightable. Sears was like Amazon a century ago, but they collapsed and were replaced without much of a fight. This isn't an industry Amazon can get a lock on and jack up the prices, because if they do, someone else can just sell the same products for less.