Far from defending Switzerland against the charge of running a half rate airforce, you raise legitimate concerns. If I wanted to invade a country, I probably wouldn't pick Switzerland. But if I wanted to invade Switzerland, being unable to afford an airforce in a time of wealth is awfully encouraging.
The question is solely political, how much money is Switzerland willing to spend for an army/airforce? And this question undoubtedly correlates with the current feeling of safety and threat of conflict.
There simply is currently no conceivable threat scenario that needs to be countered.
Second, conflicts are on a gradient, from scattered terrorist attacks to a full on military invasion, there is a lot in between.
The statement that there is no conceivable threat scenario is ridiculous.
That should be more than enough. It's not like anybody ever launched a war at 5:45 AM…
https://en.metapedia.org/wiki/Adolf_Hitler%27s_speech_to_the...
It was originally a deliberate political decision to collaborate with neighboring air forces to save costs and work around the fact that there weren't enough pilots and material ready (again a cost issue). When this was more publicized due to some incident when the french airforce had to intervene at night, everyone acted surprised, especially political parties that keep on demanding cost reduction.
Currently, the times have been extended from 6am to 10pm, and in beginning of 2021 a 24h/365d coverage will be implemented.