All of these countries save Switzerland are within the EU customs union. Being land-locked is a disadvantage precisely because you have a limited number of coun

All of these countries save Switzerland are within the EU customs union. Being land-locked is a disadvantage precisely because you have a limited number of countries to negotiate trade with and not much leverage. Countries with a port can have trade relationships with the entire world. Switzerland has always been able to/had to find a niche like banking or secrecy or regulatory arbitrage to prosper. But in theory they suffer from the same problem - limited trading partners and limited leverage.