Earlier quoted context omitted.
Switzerland is an exceptional country that has a political system far removed from the rest of the world. Democracy in Switzerland is so direct that there is a much higher level of engagement of the voters with the issues at stake. You can't take something that works in Switzerland out of that context and then apply it to some other country with the arguement 'it works in Switzerland'.
Of course you can. The above narrative clearly implied that unions are the motor of social progress while it is blantantly false. Economic development is what brings social progress. And the richest countries in the world are the ones with the best working conditions, regardless of unions power.
Not necessarily. Economic development can be limited to the owners of the companies whilst exploiting the employees. That is what gave rise to unionization, it was a reaction to abusive practices.
That unions later on became self sustaining and that they work against the interest of some of the people that are employed (seniority system for instance) has nothing to do with why they exist in the first place.