Our legal people told us that we’re okay as long as we don’t record and keep any information that could identify the person commenting. Their info is gathered by the site they comment on, but it’s transparent that they are not commenting on a gov’t of Canada site.
If we want to keep track of comments (for internal reporting for instance), we can do so as long as we never record the username or any other information that might identify an individual. That may mean redacting some words, e.g. “Hi. This video is great. My wife  and I visit there all the time because it’s close to our home in . Keep up the good work!”