Does it, how? Why would it be the vector store that would make it easier for them to censor the content? Why not censor the documents in S3 directly, or the entries in the relational database. What is different about censoring those vs a vector store?
Not to mention there is lock-in once you've gone to the trouble of using a specific embedding model on a bunch of content. Ideally we'd converge on backwards-compatible, open source approaches, but cloud vendors want to offer "value" by offering "better" embedding models that are not open source.
GovCloud exists so that AWS can sell to the US government and their contractors without impacting other customers who have different or less stringent requirements.
I do feel more and more some information in the corpus of AI models was done this way. A client's name and private identifiable information might not be in the model, but some patterns of how to do things sure seem to come up from such sources.