If a person is self-employed then he has to pay VAT (Mwst) 19%. And then they say that they cover only 60% of all the expenses. And finally the person has to pay income tax.
This is wrong. Especially if you are self-employed you do not need to pay VAT (to simplify it: VAT is for end consumers). Where do you get that 60% ? If you are not self employed you have to pay wage tax, so there's not much difference to income tax.
If you make 5k before taxes you're already way above average here, because your employer usually pays around 7k per month then.
Edit: Yes, I admit it is quite low when compared against typical contracting rates in urban areas.