The thing is, Amazon in its privileged monopoly position in practice forces you to choose between publishing exclusively on Amazon or self-publishing, at least for new authors.

This is because unless you agree to exclusivity, you will be denied access to essential marketing tools like free promotions (via the KDP program), which are essential for building initial social proof and give the book at chance to take off in rankings.

Unless you have a pre-existent audience that you can point to your Amazon non-exclusive book, there is zero chance that it will take off.