You have all the info you need in the article. Technically, Amazon's basic commission is ~15%, and that is in line with other marketplaces.

The issue is that when you pay only that basic referral fee, you won't make a lot of sales. You have to pay more to actually make those sales, which amounts to ~46%. Advertising, fulfillment, and other fees. You have to pay for all of this while being required to keep your price "fair," so you have to raise prices on other platforms to stay afloat.

You could just ignore selling on Amazon altogether, but in the US that's rather unrealistic at this point, and they know that.