i don't think any old threads should be deleted bc a lot of old topics can still be fun or helpful to read, through if you wanna find more recent posts just filter by recent
for the sake of general archiving and the fact that many still hold useful information, i dont think older threads should be deleted. after all, this site in itself is trying to preserve an old internet experience, so deleting random stuff would feel like a bit of a waste. generally i just sort stuff by most recent solely :p