Of course it can be streamed! Nobody ever suggested it could not be. The point is that to stream it portably (i.e. without knowing the hardware characteristics - and possibly software characteristics too - of the reciever) you have to first serialize it and then deserialize it, because the in-memory representation within the sender is NOT portable.

You're too hung up on in-memory representation. Yes, if it's not right, then it needs to be converted. That can be done for you, or you can do it manually with byte streams like cave man. If you can do it manually fast, then it can be done just as fast automatically based on the declared structure.

It isn't possible to be in a world where the in-memory representation doesn't matter. Someone has to write and maintain that code, and if it's you, then you get the fun task of telling some users their workload won't fit into it. And then they go off and write their own in-memory representation.