[abc03]

correction: It's a referendum (oppose a law enacted by the parliament), so you need to collect 50 000 signatures. For a petition (changing the consitituion) you need 100 000. However, the vote in the parliament was quite clear. For example, in the Ständerat 43:0, so it would have been a surprise if a referendum were launched. Swiss politics is not consensus-based. However, you don't have just two parties that oppose each other. As most parties somehow play part in the government (some more, some less), destructive behavior is frowned upon unlike in other countries. That's why maybe some think it's consensus-based. Furthermore, due to the strong federal system and general culture, minorities need to be considered. Moreover, Switzerland is a small country, which makes some behavior difficult (see also destructive behavior above).