People
think it took less effort.
Right up until you needed to do one of the very many things k8s implements.
For example, in multiple previous employers, we had cronjobs: you just set up a cronjob on the server, I mean, really, how hard is that to do?
And that server was a single point of failure: we can't just spin up a second server running crond, obviously, as then the job runs twice. Something would need to provide some sort of locking, then the job would need to take advantage of that, we'd need the job to be idempotent … all of which, except the last, k8s does out of the box. (And it mostly forces your hand on the last.)
Need to reboot for security patches? We just didn't do that, unless it was something like Heartbleed where it was like "okay we have to". k8s permits me to evict workloads while obeying PDB — in previous orgs, "PDBs" (hell, we didn't even have a word to describe the concept) were just tribal knowledge known only by those of us who SRE'd enough stuff to know how each service worked, and what you needed to know to stop/restart it, and then do that times waaay too many VMs. With k8s, a daemonset can just handle things generically, and automatically.
Need to deploy? Pre-k8s, that was just bespoke scripts, e.g., in something like Ansible. If a replica failed to start after deployment, did the script cease deployment? Not the first time it brought everything down, it didn't: it had to grow that feature by learning the hard way. (Although I suppose you can decide that you don't need that readiness check in k8s, but it's at least a hell of a lot easier to get off the ground with.)
Need a new VM? What are the chances that the current one actually matches the Ansible, and wasn't snowflaked? (All it takes is one dev, and one point in time, doing one custom command!)
The list of operational things that k8s supports that are common amongst "I need to serve this, in production" things goes on.
The worse part of k8s thus far has been Azure's half-aaS'd version of it. I've been pretty satisfied with GKE, but I've only recently gotten to know it and I've not pushed it quite as hard as AKS yet. So we'll see.