All of these complaints also seem like valid complaints about XML, except the thing about duplicate keys. Also as far as I know, there is only one "JSONSchema"

All of these complaints also seem like valid complaints about XML, except the thing about duplicate keys. Also as far as I know, there is only one "JSONSchema", and it has a clearly defined version scheme. Are there other JSON Schema standards that I'm not aware of? I'd be interested to see them.