8S and 4S servers (or even bigger systems) have always been extremely expensive; 2S has been the norm for many years. Being able to stuff two 2S nodes in 1U pre

8S and 4S servers (or even bigger systems) have always been extremely expensive; 2S has been the norm for many years. Being able to stuff two 2S nodes in 1U pretty much negates the density advantage of a 4S system, without the quadratic increase in price that a scaled-up systems have. (Also, density is usually limited by power dissipation, so the lowered power efficiency of bigger systems becomes an additional con there.)