That is not what "monopoly" means. The most famous anti-trust case was against Standard Oil/Rockefeller. At the time there were hundreds of oil companies.
Google controls over 80% of the Internet. Amazon overwhelming dominates. Plus Google and Amazon act as a team via the commonality of Jeff Bezos.
So you are a small business in Internet sales, which is over 50% of all retail and virtually 100% for many product areas. This is what you are up against - noting people shop from the top of page one downward:
Even if you are paying for Google and Amazon advertising...
Google will put Amazon above you for free. So no one pays to click on Amazon - but you have to pay $1, $2, $3 just for someone to look at your website - and people who don't buy off the top page site usually are then just looking - at your expense.
On Amazon, you will pay Amazon 15% (or more), plus $1, $2, $3 against for anyone to just look at your listing - the total costing as much as 30% of the sale.
Amazon pays none of that, plus Amazon will put their own offering of the product above yours (without the 30% cost). Even if someone clicks on your listing (you pay for clicks, not sales), where you check out there probably will be a button stating you can buy it from Amazon for less - so you spent $1, $2, $3 to promote Amazon selling your product.
Thus, you spent $4, $5, $6 to be behind and below Amazon - with Amazon consuming the sale anyway.
If you also can not offer 1 day shipping because it would cost you $35 for 1 day shipping, and Amazon will pay $7.55 cents to the post office for the same 1 day delivery.
Finally, if you have a product Amazon does not have, if you sell a lot of it Amazon will use your data and do the above to you - or just overnight ban you - as many Google - and your company is gone and all employees lost their job overnight. Of course, you can try to scramble for the other less than 20% of the marketplace - with your advertising costs off-the-charts per sale since people do shop from the top down - and the lower it goes the more you are just paying for lookers who don't buy.
THAT is a "monopoly." A monopoly means their dominance and massive size creates unfair competition.
The government just refused to allow Staples and Office Max to merge, claiming it would too much be a monopoly. Are there other office supply stores? Sure. Can people buy office supplies elsewhere online? Sure. But they would so dominate the market it is an unfair advantage.
Amazon also is the #1 location where patent and copyright violations occur, with this very much protected by Amazon. Overall, Amazon commits millions of FDA and USDA violations per day, being too big and too politically powerful to fight. The government literally has demanded we not have certain ad language on our websites - that we many have on Amazon because Amazon is immune for all laws.
Another monopoly aspect is businesses are so dependent on Amazon for Internet sales, that everyone - buyers and sellers - are required to agree that there is no circumstance by which you can sue Amazon. Amazon could knowingly sell you bottles of known poison inaccurately labeled killing everyone in your family, and all you could do is file a case with Amazon to be decided by one of Amazon's mediators.
Actually, who most has called from breaking up Amazon and Google is Elizabeth Warren - and she has explained how it works as a monopoly in great detail. It is an issue I completely agree with her on having direct knowledge. THIS ALSO IS WHEN HER FUND RAISING CRASHED AND SHE RADICALLY DROPPED IN THE POLLS. She dared challenge media owning Amazon and Google, so they crushed her campaign. People wonder what happened to her campaign. Jeff Bezos happened.
IT IS AMAZON, GOOGLE and their media power that crashed Warren's campaign after she said she would use anti-trust laws to break them up their components into separate companies. She has never been brave enough to even mention Amazon or Google ever since. They not only totally control the majority of retail sales, they control the government and politics.
Your defense is not on any knowledge. As for the overall effects and realities? You haven't a clue. Don't even think about patenting a new consumer product. Within a week it will be copied in China with 50 listings above yours on Amazon - with Google putting the cheap Chinese knock-off above your's, and if Amazon is selling it they'll put it above your listing no matter how much you pay - until Amazon and Google ban you entirely.
The ONLY products we sell on Amazon are hazardous materials or that we uniquely manufacture. Amazon does not have hazardous materials at Amazon Prime warehouses and so far no one can even duplicate the other product line.