In theory yes but if a private institution has a lot of market power like amazon has they can effectively shape the public discourse with their censorship. Which indicates to me that big operations are dangerous for democracy.

Then maybe we should cancel big television or news networks.

Nowadays, every one of them are not even pretending they are unbiased, how is that better than take down 2 books selling pseudo science? And do we need a democratic process to decide whether certain treatment is acceptable?

That smells suspiciously close to the anti-vaxxer argument.

Amazon doesn't sell Nazi flags. Is that censorship, and does that keep such flags from public discourse?

You are making a straw-man argument. Nobody here is claiming Amazon should be forced to sell a Book. The concern is whether it is a right thing for Amazon to do, not whether Amazon has the Right to do it.

Here is what the grandparent comment said:

> Should Amazon, or other intermediaries, be allowed such interferences?

It's not a strawman to read that, then ask:

> Shouldn't a merchant be able to decide for themselves which products they want to carry or not carry on their shelves (both physical and digital)?

> Is the alternative that a merchant should be forced to carry a product against their will?

edit: formatting

Of course they should be able to, but that's not what OP asked.

Sorry, I misread OP. People treat "should do" and "should be able to do" frequently as the same thing in these cases (Twitter and "free speech" is another such case).