IMHO, your reaction is odd. What is wrong about keeping a post for seven years? Even older posts have been saved on FR and can be found with just simple research.
What I found odd about it, Dante, was the petty nature of the reason for it. Certainly, posts have been saved that are informative, or that indicate that the poster was on to something important at the time.
To save a post for 7 years for the purpose of “getting back at” someone in a nasty and personal way strikes me as bizarre and rather childish.