You have a point. Indeed, the practice of building specialized machine or container images, which seems to be the best way of achieving immutable infrastructure

You have a point. Indeed, the practice of building specialized machine or container images, which seems to be the best way of achieving immutable infrastructure, may make servers more heterogeneous, since each image will contain only the pieces necessary to perform its specific function. Done right, immutable infrastructure may be more resilient in the face of parasites.