Our forgotten immune system

Between the sheer quantities of medications that we consume each year, the surgical disinfectants that became household items, and the fact that most of us run to the doctor at the first signs of illness, makes one wonder about the role of our immune system.
Muscles weaken through disuse, and our immune system atrophies if not challenged.
We forgot that we have an internal pharmacy ready to help us at the slightest sign of weakness.
Instead of weathering the storm and letting our immune system take charge of restoring us back to perfect health, we open our bathroom’s over-stocked pharmacy cabinet, and take anything that would assuage any unpleasant sensations that we might be experiencing.
Our immune system takes note of that and moves to the sideline to "relax", because its services are not needed anymore.
Our body are very economical in its functioning, it tends to prune anything that is not useful, to avoid wasting energy.

The "pruned" parts might include our immune system's basic functions.
Mild exposure to germs gives our immune system the "workout" it needs to get stronger, and be able to fight off diseases.