I think it is constitutional. The arguments you've raised are more political in nature. You gave the example of your spouse, who is one specific case, but the Constitution applies to the entire community and the Canadian population as a whole.
Based on your reasoning, you would be against all the measures that Quebec has taken to promote French because you would consider them unconstitutional. You would say that the criterion related to knowledge of French to select immigrants to Quebec is unconstitutional. It's the same thing.
We don't prevent people from communicating with the government in English or French. All we want is an incentive. We want people to demonstrate that they know French. The Citizenship Act already requires knowledge of English or French, and if a person does not have knowledge of either language, their application is rejected.
We believe that in Quebec, knowledge of French should be required of immigrants because it is the common language. This doesn't mean that it's not important to know English or to be bilingual on an individual level. In Quebec, French must be strengthened. I don't want to get into a political debate, but in Montreal, French is on the decline. The indicators show that there is a decline in French because newcomers are not sufficiently francized. It's not a far-fetched requirement that we want to use to crush anyone; it is a requirement that aims to ensure the future of French in Quebec.