Extirpation (removal) of 'sold, dead or no activity) threads

[WallyR]

Hi guys (Admins)
Only been on the overall forum for a few months.
Love it, but keep finding threads (on various forums), that haven't had any activity for months - sometimes years.
Then some weeks/months later, the same item/subject crops up again as a 'new' thread with a slightly different title.
I'm under the impression (possibly false), that Administrators are 'supposed' to keep threads as current and up to date as their time allows.
Some forums have over 1K of threads going back 2-3 years.
Seems to be a waste of 'processor' space - and memory, to have non-active threads hogging memory.
Elsewhere, Admin. means 'control and keeping up to date'.
Just my 2c worth.