While I agree with the premise, I don't see how this specific event ties to your argument.

A simple Google search shows that the referendum passed with 57% of the voters support, so that leaves us with a 43% who thinks it's a bad idea for one reason or another. Since around 5% of Switzerland is muslim, one could argue building minarets is not such a scandalous idea for Swiss voters.

The direct consequences for Muslims are hardly the problem here – only about 30 women in Switzerland (we know about) even wear a burka/niqab and quite a few of them are Swiss converts. Back when we banned minarets, we had like three (!) of them in the whole country. But we had ads like these [0] all over the country for months again and if that doesn't give you the most profound chills, I don't know. It's textbook right wing scapegoatism and I'm pretty sure Muslims can feel the very real consequences of that kind of propaganda.

[0] https://verhuellungsverbot.ch/downloads/

They voted for the ban today. France showed that it had little positive effect for women.

The University of Lucerne ran a study and came to the conclusion that there are around 20-30 women in all of Switzerland who wear a niqap or a burqa.

That had nothing to do with "separation of church and state". It was banning private individuals to use a specific form of architecture. Pretty much any country in the world allows building mosques with minarets... did they threaten anyone's liberty / change their culture?

Going back to GP's point, the deeper issue is that people thought this was worth writing in the constitution. Other countries apply such laws in different ways, so I don't think the Swiss direct democracy is to blame here.

Asked out of genuine inquiry and curiosity not to bait (I know it can be difficult to tell online): The referendum was simply to add the words "The building of minarets is prohibited" to the constitution. This only affects someone who would wish to build one (so Muslims) and in my mind says that your type are less welcome here. Why would Christians be negatively affected by this?

I would take the view that banning the form of your religious buildings (and implicitly, to your comment, being hostile to Muslims who in your response you seem to equate with a culture that destroys the possibility of liberty) seems more of a betrayal of the principle of liberty and freedom for all than allowing different people to pray and associate as they wish, providing they follow basic tenants of human law (not harming people etc).