That's the same with.. the Linux kernel? I'd wager that most services people write have less complexity than the the kernel it runs on. We choose to do that not because we need its full feature set, but because it gives us useful abstractions.
If k8s were as complex as it was, but didn’t force that complexity onto the user, I’d agree.
I can understand that it doesn't come off that way but I actually like k8s and the surrounding ecosystem. But deploying k8s makes your infrastructure as complicated as k8s itself, which can be a massive win because it works in both directions.
I believe the OS comparison is the most apt, both in the sense of the layer it represents, i.e. abstracting away physical machines and managing resources for applications, but also from what it means: one used to have to rewrite a program for each new computer as they were all unique (incl. CPU), just like each corp had its own way of managing infrastructure, clusters of nodes and automation.
Any new application needed to be integrated from the ground up, which might be simpler in that you only touch what you actually need, but you also have to do it every single time, and it's different for each project/corp - with the vast majority missing out on the more complex bits that don't fit into an nginx config and some shell scripts.