Thanks to your post, the comments and the discussion that ensued, I was able to recreate the same effect on my Wordpress blog: https://www.lealternative.net/2024/10/21/cal-com-infrastruttura-di-pianificazione-per-chiunque/ 🧡

Thank you for your answer!

Since I currently use Hetzner the only way to get more space is to upgrade the server (at a not inconsiderable cost).

The alternative might be to purchase SSD block storage volumes which are definitely lower priced (5€ per month for 100GB) however it would be interesting to know if there is a guide for Lemmy for this or if others have had positive experience doing this.