The real meaning is lost in translation.

It's one of three things for me.

1) The author feels Ubuntu is becoming the Microsoft of Linux and he will not continue to support it based on ethical reasons.

2) The cost of supporting and maintaining quality free software takes considerable effort and time. You have to be altruistic in every sense of the word to be an open source developer. People expect and sometimes demand you keep pace with every release of Ubuntu and be technical support/troubleshooter for them. All of that for free.

3) He hates Unity and is moving on (like I did). Just kidding, Ubuntu, err I mean Lubuntu is great.