Do you mean geocoordinates when you say not human readable? Those are obviously at the heart of geospatial information but there is quite a bit more to the spec that does benefit from being human readable, and I'd include longitude/latitude among them. There are also solutions like cbor which allow them to be transferred and decoded/encoded from binary. For performance critical data you can also use something like protobuf, but it would be a huge pain to handle everything that way. Json is a great choice as a general spec.