There's your problem! You're not a typical user. How many iPad users are currently looking to replace software that was replaced (for most) by Adobe Illustrator and Microsoft Office over 30 years ago? Kids these days don't know MacDraw from Quickdraw from QuickTime... if they've heard of them at all. A curated App Store would be even less likely to help you.

I don't blame the App Store for not knowing about MacDraw, just like I don't expect it to have an "Algol 60 replacement."