You’re paying for resource isolation. You can put many things on 1 server and it will be cheaper. We have done that for decades.

Managing that can quickly get cumbersome, especially when you deal with software that wrecks easy mode of "just install mod-php from distro packages". Ensuring resource allocation was also much more annoying.

Letting scheduler handle allocation of many services onto few servers is how I managed to pay only 10% of what was the previous cost.