The only mention I can see in this document of compression is

> Significantly smaller than JSON without complex compression

Although compression of JSON could be considered complex, it's also extremely simple in that it's widely used and usually performed in a distinct step - often transparently to a user. Gzip, and increasingly zstd are widely used.

I'd be interested to see a comparison between compressed JSON and CBOR, I'm quite surprised that this hasn't been included.