I like having old posts show up in my sidebar. I know about the evergreen theory where posts should never get stale, seasonal, etc. I just don’t agree with it.
I’ve been using the Time Machine plugin for several years. It sets up and works without much fuss. You can forget all about it there among your widgets.
Of course, there are other plugins for the same idea of looking back a year into your site’s life. I’ve put together a list for you to explore. (At this point the only one I can personally recommend is Time Machine).