Thank you for your question.
While that ranking is interesting, it is not a useful scale. The scale is based on legal frameworks rather than operational realities. I do not think anyone believes that Russia or Afghanistan are more transparent than Canada because they ranked higher.
It is also noteworthy that this ranking does not consider proactive publication either which, as you said, is essential to a strong access to information system. It was noted earlier that the global data barometer ranked Canada seventh for open data.
I think Canada should continue to examine this.