It was an experimental feature slapped together by pg in 2009, and has been largely forgotten about ever since. The motive then was to see if there was any difference if you filtered out newer users. There wasn't then, just as there isn't now.
Its continued existence is just a historical artefact.
As far as I can see it's not linked from anywhere in the UI, and is only occasionally referenced in comments.
> a view that only counts votes from accounts which are more than a year old, or some other criterion which reduces young and drive-by accounts
Are you sure you know what the motiviation for accounts older than 2008 is (are you sure it's reducing young/drive-by accounts?)
Have you thought about what that motivation might be?