I'm a long time software engineer and do quite a bit of devops both in cloud but also have significant experience building on-prem and datacenter server clusters.
I have never heard of IBM i until this moment right now.
I assume this is specifically for their Power-series hardware? I've only ever seen Linux on Power hardware...
You may have known IBM i under a different name such as eSeries or AS/400 as it has gone through many renaming.
Yes, it currently targets their Power series, although it's fairly hardware independent. As a matter of fact AS/400 binaries don't even care what CPU they run on, as there are several abstraction layers underneath, namely XPF, TIMI and SLIC. It's a bit like a native, hardware-based JVM with the OS being also the SDK. Another peculiarity is that everything is an object in "i", including libraries, programs and files.
But mostly, it requires close to no sysadmin. Just turn it on, start the services and leave it alone for years if needed.
I have never heard of IBM i until this moment right now.
I assume this is specifically for their Power-series hardware? I've only ever seen Linux on Power hardware...