I feel that author is very enthusiastic, but there are some pretty serious errors:
"... fight between Docker and systemd is inevitable" -- this fight has been going for a while (at least a year): https://lwn.net/Articles/676831/
"... The reason why you'll do this, rather than compose everything yourself, is compatability. Whether it's kernel versions, file system drivers, operating system variants or a hundred variations that make your OS build different from mine. Building and testing software that runs everywhere is a sisyphean task. " -- kernel versions, file system drivers, operating system variants (in form of docker daemon version) are still going to be around and would still affect containers. So you traded "test on Fedora, RHEL, Ubuntu" with "test on AWS docker, Tectonic, OpenShift". Yes, you no longer have to worry about .so versions, but there are still plenty of reasons to test in multiple environment.
"... the operating system is an implementation detail of the higher level software. It's not intended to be directly managed ..." -- yeah, so I have this proprietary SAN.. or a dual 10G cards which need to be tuned and bonded... or a mix of fast and slow disks... or even any non-trivial RAID setup... Those things are the most annoying parts of managing your own servers and unfortunately they are not going anywhere.
"... fight between Docker and systemd is inevitable" -- this fight has been going for a while (at least a year): https://lwn.net/Articles/676831/
"... The reason why you'll do this, rather than compose everything yourself, is compatability. Whether it's kernel versions, file system drivers, operating system variants or a hundred variations that make your OS build different from mine. Building and testing software that runs everywhere is a sisyphean task. " -- kernel versions, file system drivers, operating system variants (in form of docker daemon version) are still going to be around and would still affect containers. So you traded "test on Fedora, RHEL, Ubuntu" with "test on AWS docker, Tectonic, OpenShift". Yes, you no longer have to worry about .so versions, but there are still plenty of reasons to test in multiple environment.
"... the operating system is an implementation detail of the higher level software. It's not intended to be directly managed ..." -- yeah, so I have this proprietary SAN.. or a dual 10G cards which need to be tuned and bonded... or a mix of fast and slow disks... or even any non-trivial RAID setup... Those things are the most annoying parts of managing your own servers and unfortunately they are not going anywhere.