Our site is updated regularly, but a major overhaul took place over a year ago and so a lot of folders were added to replace the existing ones. Reason was SEO, meaning new folders had better descriptive quality.
As such, the old default.html pages have 301 redirects to new location.
Can they be deleted after 'x' time or should they remain? Low traffic site and unlikely anyone bookmarked them.
I get "no harm done, just leave them alone", but doing clean-up also has virtues. Also, is there a plus or minus SEO impact from deleting them.