It of course also creates essentially perfect competition. Amazon will even tell you the top selling products across categories, so that no seller can make excess profits for long - others will quickly jump into the fray to compete that away.
This is of course the market working as intended - the sellers compete away any and all surplus. Normally that would be a good thing for consumers! Unfortunately the search ad tax is very real, and siphons off a good chunk of the surplus as monopolist rent.
This is all structural. A marketplace like this is a natural monopoly with massive network effects. And the allure of the search ad is irresistible - they literally can't not do it, lest their shareholders rebel.
Google ads work exactly the same way.
As a seller your only options are to either have better conversion economics than the competition (so you can win the ads bidding war - guess why every successful site on the internet is gameified to all hell, and why the amazon listing titles & descriptions look like they do) or to not play.
If you can create a viral hit for a product you can probably eke out excess profits for a few months - people want precisely your branded product and not a cheap knockoff, at least for a while.
("Excess profits" = anything above what will literally make the marginal seller say "it's not worth it", which is a very low bar when competing with the entire world)