Excellent column, thanks. Freedom of speech often isn't given enough respect in Canada. If we find the opinions voiced by these people objectionable (and they really are loathsome in this case), it's up to civil society to oppose or ignore them. The government should not be in the business of deciding what can and can't be said in our public spaces, with extremely limited exceptions.
I see the old "you can't shout fire in a crowded theater" line has already been used in the comments. People should look at what a disgrace the Schenck v. United States case, from which that line originates, was as an example of how dangerous it is to allow government to decide what is and isn't permissible to say in a public forum.