Shoes.

Coats.

Chairs.

Beds.

In the name of comfort & ergonomics, the more these things do for your body, the less your body has to do for itself.

Ultimately, this makes you less resilient.

Buyer beware. 

 What alternative would you suggested instead of a typical bed mattress? 

 Good beds are well worth the trade off imo. But if you want to experiment I know some people use gym mats similar to those used in mixed martial arts or gymnastic gyms. 

 Interesting idea. Recently upgraded from a queen to a king, but my sleep has been terrible since the queen was a stiff spring, and the king is a 'firm' foam. So need to find a solution. 

 Temperpedics are 👌🏼 very expensive but they usually give you a line of credit with 0% for 2-3 years. Worth give you’ll spend a third of your life sleeping.

No mattress sometimes is better than a bad mattress 

 Indeed nothing is without trade offs. No free lunch in this world

One can optimize or adapt. Both have their role