You have found AmazonBasics that were counterfeit of fake? If so, that's a pretty big deal. Amazon is slapping their logo on those products and presumably doing QA. They are also the only company allowed to sell them on Amazon.
Not to be confused with Amazon's Choice. Which means jack squat.
I've had Amazon Basics cables that weren't up to spec, yes. In fact most Amazon Basics electronics products have been poor quality of those I've purchased (mostly cables and a couple sets of speakers) so much that I won't even buy anything labelled as such now.
Not directly addressing your question, but Amazon did a recall on their own chargers included with UK and Ireland Fire tablets, and recalled over quarter of a million portable AmazonBasics chargers.
Not to be confused with Amazon's Choice. Which means jack squat.