Adobe's current policy generally only allows for the download of the and the one immediately preceding major version (N-1) via the Creative Cloud desktop app. Since Illustrator 2021 is now several versions behind, it may not appear in your standard "Other Versions" list unless you already have it installed or are an enterprise user with specific permissions. How to Access Adobe Illustrator (Free Trial) Illustrator Free Download & Free Trial - Adobe
Adobe Illustrator 2021 (version 25.x) is not officially available as a standalone "free download." However, you can access the latest version of Illustrator through a from the official Adobe website .