In the 90s, most of the Delphi program was always connected to the database server, in a fully-connected scenario. In this situation, dataset serialization was a nice topic. Today, the software world is heterogeneous—different operating systems, programs, and languages must still find a way to communicate and exchange data. We are in the IoT and big data era now!
Now a days, making your data available to other programs or getting data from other software running somewhere in the world is bread and butter, so you can understand that using a proprietary or exotic format is no longer enough. To better understand, the dear and old Dataset.SaveToFile may not be enough.
Let's say we have a JavaScript frontend for our Delphi application server. Your data should be deDelphized (I've just coined this word) and should be independent...