"A few systems that support LXC", that's actually most modern Linux systems now. Anything with a 3.8 kernel is game.
So Linux systems, that started shipping just this year?
Well but even that is not true because it was backport-ed to RHEL 6/CentOS 6 which is very cool.
Not all people live dangerously and install the very latest release on their server.
Ubuntu LTS (which is a common server platform) also doesn't natively support LXC well. It has an older kernel. So instructions for installing docker is to install a new kernel. A new custom compiled kernel on a production system. Hmm, is that still Ubuntu 12.04 LTS, some devops will argue it isn't, some will say it is fine.
I would rather see that too. So we agree there. If you read my comment, it was about making ridiculous statements about compatibility, not that I want or need more compatibility.
On a more general level it is about being dishonest and how ardent fans are enemies in disguise. They make ridiculous statements about the product that then creator of the product end up having to manage the PR.