They are completely landlocked by the EU and their Airspace.
Also most of their imports/exports go there.
They don’t even farm enough to sustain themselves. So yes, obviously it’s true
Landlocked does not mean dependent.
They also are not completely dependent which 100% means.
Last time I looked into imports and exports of countries Switserland was around 50-60%.
I mean they mostly are, they’re approx. 50% dependent for agriculture, so if the EU were to block all borders and halt all exports to them the Swiss would become significantly skinnier than they were before.
No shame in that by the way, the Swiss also provide the EU with lots of stuff and services that are valuable.