And do the same with every other renegade, including reciprocal mirror tariffs and stuff. Want to play games? Let's play them together.
Not really, the bilateral are a package and the EU doesn't want CH to pick and chose.
If freedom of movement stops, a whole lot of thing also stop. It happened the last time SVP got something similar voted on (introduction of quota for foreign immigration), on a smaller scale (erasmus and horizon which are the higher ed and academic research collaboration, CH was a heavy recipient of the latter).
It really depends who is in power where when and if the 10mm limit is crossed. If there is a conservative in Paris or Berlin, chances are Switzerland can simply abrogate Schengen.
Of course if you have EU dismantlers in power anyway in FR/DE, they'll just be happy to sabotage.
I think we do bilaterally with our trading partners/border friends.
Freedom of movement across the EU has created a massive backlash. Politicians can keep ignoring that. Or they can modify Schengen, perhaps by admitting that FOM makes immigration decisions a collective one. (Germany letting in a massive wave of immigration means a massive wave of immigrants for everyone.)
I say! That's news to most.
March 26, 1995 (The Implementation): The Schengen Area officially became effective on this date. Internal border controls were finally lifted among seven member states.
Everything else is negotiated under separate treaties. This would revert Switzerland to pre-Schengen, which is sad, but it wouldn't be suicidal.