Why can't RTCDataChannel transfer byte arrays directly?

[TenSpaces]

I want to transmit JSON strings continuously through RTCDataChannel, and the size of the string may be different each time, so I use RTCDatachannel. send(RTCDataChannelBuffer buffer), But I found there is a RTCDataChannel method can direct transmission byte, it is RTCDataChannel sendByteArrayBuffer (byte [] buffer, Boolean binary), but this method is private.I wonder if this method should be set as shared?