When moving to the cloud, the four pillars become much less manageable. The amount “much less” implies depends a lot upon your cloud provider, and how you define “cloud”.
Put in simple terms, if you are suddenly struck blind, that does not change what’s in front of you, only your ability to perceive it.
In the PaaS world, you have only the tools the provider offers to measure these things, and are urged not to think of the impact that host machines may have on your app. But they do have an impact. In an IaaS world you have somewhat more insight, but as others have pointed out, less control than in your datacenter.