There is an optional feature on Mastodon which lets you automatically delete your posts after a certain amount of time:
➡️ https://fedi.tips/deleting-posts-automatically-in-mastodon-after-a-certain-time-period
If you activate this, your posts that are older than a certain number of weeks, months or years are automatically deleted by your server.
The setup process for autodelete also lets you choose types of post or specific posts not to delete.
(If you want to keep everything, just don't activate autodelete 🙂 )
Edited 9d ago