Our system of labour laws simply doesn't work in the public sector or the extended public sector. By contrast, in the private sector, both management and the union face the very real threat that an extended labour disruption could result in the permanent loss of customers served by the business and, ultimately, closure of the business. That reality tends to get people on both sides focussed quickly on what it will really take to settle. There are no such motivators when government creates monopolies over spectific kinds of work. In a public sector strike, the government entity actually SAVES money, as their budgeted support from treasury is already written in stone. They get their money whether they perform a service or not. The union doesn't have to fear that their work will be redirected to a competitive service. They can essentially hold the public hostage, courtesy of public sector labour policy. The only people who suffer from such strikes are the public who rely on these services.
Canada needs to be able to admit we've made a few mistakes along the way when it comes to public policy in labour law. Unfortunately, to the left "progress" never means fixing mistakes. It always means doubling down on the same mistakes.
Unreliable postal service is just one of the infrasture deficiencies that discourage business investment in Canada.