Well, it's easy. It's like that virtually in any other country. In other countries you act like an idependent contractor - in German Selbständig. Therefore you take your revenue from RYR, deduct your expenses and calculate profit. From this profit you pay the social contributions and taxes. Therefore there is an over 95% retention rate in the first years (due to the type rating costs) in countries as Spain, Italy, Poland, Czech Republic etc. In Germany, on the other hand, you can't act as Selbständig if you're a pilot. Therefore you need to kinda employ yourself and pay both employer's and employee's part of the social contributions. What's even more bizzare is that you pay 1.9% of the gross salary as sick leave insurance (Arbeitsunfahigkeitsversicherung) but if you're sick, you won't get any money. It's because the employer is supposed to pay this money to the employee but as the particular pilot is both ER and EE, he won't get a dime etc...
Long story short, Germany is pretty exceptional on this. I would rather act as standard German independent contractor and pay all the contributions in here including the taxes but unfortunately it's not possible.
In terms of the health insurance. Both options have pros an cons. The one who says otherwise is definitely not objective. One can save quite a lot of money when he is young / has small or no family. On the other hand.... Wait until you're 65. I know people who are retired an pay around 900 - 1000 EUR per month for the premium. Thats 12k EUR per year, 240k EUR if they gonna live until 85. All of this with no other income than the pension.