OpenStack immature? Man, this was in 2014... We're in 2022. OpenStack is 11 years old, and it runs very well.
Also, adding the word "crap" in all sentences doesn't buy you anything, and make me think you're the immature :(.
For someone that operates it, it's probably correct that it's hard to tackle. I wouldn't leave someone in charge without at least one year of experience using it. However, for someone using OpenStack, it's an administrator dream becoming reality. Servers are popped up in a matter of seconds, when it previously took hours to setup physical hardware. OpenStack is also very feature reach. "Just an haproxy" you say? Well yeah... just an haproxy that runs on 2 VMs with a VRRP port to handle failover. Failovers which are transparent, so you can easily spawn a new pair of VMs. It would take you days to setup by hand. And everything is like this for all other services. All you're getting is "just" automations, but at the end of the day, this is what the cloud is about.
What's right in what you wrote, is that people are building software the wrong way. It should be packaged, and deployed anyways an admin wants, and never forced into containers / k8s. This should be an administrator choice. But hey... devs are NOT admins, so they don't know. You just need to teach them...