People were convinced that Mongo was a good choice as a default, general purpose db, when it clearly wasn’t for about a million reasons.
I don’t think DynamoDB is marketed or viewed in the same way. The docs are pretty clear about needing to design your data model to specifically work well with Dynamo. People using it seem to generally be aware of its limitations, and deliberately choose to accept them for the sake of performance and scalability. At least that’s my perception.