I’m concerned that your preferred solutions may ignore the needs of working with peers. When I’ve worked with similar solutions before, we had a lot of on call, and it all went to the same person, regardless of who actually answered the phone.

Totally hear you and have the same experience myself. The approach I'm advocating for is simply running a binary on a server with rsync to deploy, and architecting your product around that limitation. Teaching a team the basics of Linux sysadmin will be incredibly useful for their careers, and it's something that the whole team can easily learn. Then you don't need to hire a k8s team -- any engineer can do some basic debugging when things go sideways.