Yeah… when I go to this page:
https://kenney.itch.io/assetforge it says $19.95 and “You own this software Purchased for $19.95 7 years ago“, which is correct.
When I follow the link to deluxe:
https://kenney.itch.io/assetforge-deluxe it says “A downloadable software for Windows, macOS, and Linux $39.95 USD or more”
Clicking on Buy prompts me to pay $39.95, which I see is the same price as on https://www.kenney.nl/tools/asset-forge#buy