Being a high-rank member doesn't necessarily mean having a good judgment on how good/bad a post is.
There's a lot of Sr. Member and even Hero Member who still do a shitposting on this forum and it doesn't quite reflect their position as a high-rank member.
Which is a problem this change is intending to approach.
Ranks will be gained not only by sheer amount of posts, but also by quality standards.
Why doesnt theymos take them away from everyone now, why do those that already have achieved their position keep it?
Well, the public outcry from a change like that would be...I dont even want to think about it.