I think he speaks for sysadmins. If you are using cgroups at the moment you can write scripts for them. It's a mounted filesystem. The change forces you to use systemd for cgroups as only systemd is able to write to cgroups. The argument is: If you don't like systemd implement an alternative that does this for you. Some for kdbus and udev, netlink...
The article is right - it's not Linux as we know it anymore for better or worse.
That is the change that kernel wants, not systemd.
They want to prevent direct access to Cgroups, other than through a single writer. This change is happening regardless of whether you want systemd or not.
You are right. I remembered reading an article from 2013 that gave the impression that the changes where related to systemd and then it shed a different light on the issues (https://lwn.net/Articles/555922/) but it looks like the features are mostly back and in a better shape: http://lwn.net/Articles/601840/
> The change forces you to use systemd for cgroups as only systemd is able to write to cgroups. The argument is: If you don't like systemd implement an alternative that does this for you.