Swiss banks doesn't actually disclose to swiss authorities, even though the have a wealth tax based partially on the money in your bank account.
(i'm swiss)
I believe there is no way in hell they could have passed this legislation if it included giving data of swiss citizens to the swiss government.
People here cherish their banking secrecy and it's still somewhat part of the national identity.
From a swiss point of view it was/is pretty much: The US is pressuring us too much, we'll have to give up banking secrecy, but only for foreigners.
If they didn't do that, i'm fairly certain it would have been shot down by the people with a referendum.
Exactly, this is also what neighboring Austria did a few years ago.
It is nice that Switzerland takes the attention for "banking secrecy" because other countries that have it in law get to fly under the radar.
As always, people that have better reading comprehension skills get their advantage.
If you even fake documents to avoid taxes, then you can end up in jail.
This system of "voluntary" tax declarations is like a contract between the government and the citizens: Government doesn't stick their nose into bank accounts of citizens, while citizens pay taxes on their assets. I'm not sure if it's a good system, but it has mostly worked out so far.
Hidden money cannot be spent and as soon as it surfaces you would have quite some explaining to do.