No, it really is not a problem. Amazon does not have a monopoly on consumer purchases. If your livelihood is dependent on selling on Amazon, a company which sells tons of products first party, then you need to be prepared from day one for the possibility that Amazon is going to bring a product to market in your category under the Amazon Basics brand, or that they will go directly to the manufacturer whose products you are selling.
Period.
Amazon isn't running their business so you can make money. They're running it so they can make money. As long as they think their interests are aligned with yours, then there's a chance for you to participate profitably on their platform. The minute that changes, you better have a plan B.
To operate a 3rd Party Marketplace while also harvesting said marketplace's data and then deliberately targeting top products, killing those 3rd parties in the process?
I just don't get it. Do you think someone selling a generic product that only differentiates on price has some unalienable right to make money on Amazon.com? Or that some wholesaler buying branded products has an inalienable right to somehow not get squeezed out when the only value they provide is placing POs with a vendor?
It's not about what intrinsic value any particular seller can bring - it's whether or not Amazon has become a defacto monopoly and/or practices anti-competitive behaviors.
It's not anti-competitive behavior, it's just ordinary competitive behavior. Sometimes Amazon decides to compete with the sellers on its platform, and woe betide them when it happens because Amazon is an extremely competitive business.
Anti-competitive behavior is when you interfere in someone else's ability to compete with you. No amount of outcompeting competitors can make a business anti-competitive. It's almost a tautology.
Is there evidence of Amazon driving a company out of business by abusing this position? If there is then that could be a problem.