How would you classify VPS and dedicated servers though? Aren't those considered infra?
So while you can build your own IaaS by using dokku, Kubernetes or whatever on top of dedicated servers, dedicated servers (or VPS) by themselves aren't part of IaaS.
> Infrastructure as a service (IaaS) is a cloud computing service model where a cloud services vendor provides computing resources such as storage, network, servers, and virtualization (which emulates computer hardware). This service frees users from maintaining their own data center, but they must install and maintain the operating system and application software.
That's literally openstack, which is basically the definition of IaaS