Sure, you have to work to target your own audience and build the trust with them yourself, but it's a tradeoff that benefits you in the long run. Your not beholden to the whims "the platform" as many media companies learned the hard way by putting so much of their focus on Facebooks platform in the past decade.
I think to some extent Amazon's commoditization of 3rd party vendors has hurt customer confidence, though surely not enough to make up for the increase in revenue.
Amazon has a HUGE fake products problem.
The brand is damaged and getting worse. People already avoid Az and it will only get worse.