It's not just kubernetes and openFaaS, what about that thing that's a virtual appliance and requires a VM, now you need KVM. Network and firewalls? Storage as in fully replicated cannot ever lose a byte or have it unavailable storage? Object as well as block. Databases, point in time restores/backups/automated maintenance for postgres and then you've probably got a mssql server for that one app, and mysql for that other app.
It becomes just a fairly massive task back in the real world.