They are doctors which means that they mostly see sick people so their opinion is biased.

The reality is that most people don't get sick.
There is plenty of research that supports this.
My favorite is "world population has doubled since about 1970".
This would not be possible unless most people don't get sick.
How about the 80/20 rule that states that 20% of the population accounts for 80% of healthcare cost.
This would not be possible unless 80% of the population is illness free.

If you do this research long enough you will arrive at the conclusion that having a robust immune system IS the norm.

And realize that health insurance would not work unless this IS true. If being sick were the norm, an insurance company would never collect enough in policy revenue to pay the healthcare invoices.

Super human immunity is not "super" . . . it is normal.