"Except that in JSON, strings need to be surrounded by double quotes"

This is a funny limitation, since JSON came from Javascript and {a:1} is perfectly legal in Javascript

"Why impose on human readers a syntactic requirement that only compilers/interpreters need?"

Well, for human readers this can be bad, but <> can be bothersome as well.

YAML could be a better choice (or something similar to JSON but with better syntax)