That has nothing to do with ethics. It’s simply economical, and the economics of arms sales to European countries have fundamentally changed with the revival of Russian imperialism and the Ukraine conflict.

Apart from countries with imperial ambitions, countries typically arm themselves for defensive purposes in order to ideally deter possible attackers from attacking in the first place. Pretty much any country with a potentially aggressive neighbour was facing the same problem laid bare by the Swiss refusal to sell weapons to countries supporting Ukraine after the Russian invasion: The moment you are involved in a conflict, even if you’re just defending yourself, Switzerland won’t sell you any of the stuff they were happily selling to you before.

So why even buy weapons whose supplier will refuse to sell you any more in case you actually have to use them? Isn’t it better to buy them someplace else, where you have a good chance of the supply not drying up the moment someone invades you? I guess the Swiss arms manufacturers (of which there are plenty) did notice a sudden reluctance of their regular customers to buy, and went to the government to complain.

Especially with all of Europe rearming in the face of being abandoned by their former ally across the Atlantic, that’s just a business opportunity too big to ignore.