Currently, in order to report the contents of a data container, some other function needs to be leveraged to stringify before output, e.g. storejson(), format(), string_mustache(). It would be convenient (at least for examples and debug reports) if you could directly expand a datacontainer (e.g. reports: "$(my_data_container)";)
See this discussion in a PR adding an example to core about style.
I prefer multiline for human readability, but others might prefer serialized for compactness.
I could see this also being useful for writing a data container to a file or using a data container as part of a command perhaps in some API call.