There is a link on the main page titled "Decolonizing Functions", which leads to... https://meta.wikimedia.org/wiki/Special:MyLanguage/Abstract_... I'm not sure if that is satire, or for that matter this whole site.
Your outrage at this seems to be analogous to outrage of people who think that it is horrible that Unix has a "kill" operation. Basically, you don't understand that "decolonization" is a metaphor for a broader historical perspective, and instead you're trying to interpret it literally and in a bad faith.
The reaction is more similar to people who ARENT bothered by the use of kill, master, etc. The article about “decolonizing” functions is a shoehorned idealogical venture. A completely unnecessary political aside.
I also wouldnt call it outrage. That just seems like a way to make the point sound unreasonable without addressing its logic. If his reaction is outrage then so yours.