You are wrong, actually. Please read https://developer.amazon.com/amazon-drive
Amazon Drive API access is only by invitation. If you do not have an invitation you cannot even see the API, let alone use it. We don't have an invitation so that discussion ends right there.
Moreover, they only allow "supported use cases". I wouldn't believe that "Really big backup archive files of sites that are going to be sitting on your service forever" would be a supported use case. The reason is rather simple. They offer you "free, unlimited" storage. Last time I checked hard drives cost a lot of money and they have limited storage. So Amazon is footing a really large bill. Why? Because you and your data are the product. By scanning your media and documents they know what you want before you even know it yourself. This information is used for targeted marketing which means that you get to buy from them and pay for your data storage (and turn them a good profit). Shoving a large, bespoke format archive of a site doesn't let them monetize your data. So that wouldn't be a supported use case.
In case you're wondering why Synology's use case is supported since it's so "similar": it is not similar, at all. NAS are primarily used to store media and documents, i.e. things that can be analyzed to figure out what you're interested in. See how different is the expected data you're going to store in each case?
We can request an API invitation but I don't think we'll ever get a positive reply. Don't hold your breath.
Nicholas K. Dionysopoulos
Lead Developer and Director
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