Is it possible for a non-administrator user to delete an app which that user installed from AppStore on macOS?
It is possible a non-administrator user can remove an arbitrary folder, but not guaranteed. The permissions model will show your permissions on the folder.
Your last shows the directory is locked to everyone except the owner. You are correct you need admin to change that.
The App Store generally doesn’t drop a folder, so you might need to open a support case with someone or disclose a screen shot / output shoeing your precise setup for someone to tell your specific case.

https://support.apple.com/guide/mac-help/change-permissions-for-files-folders-or-disks-mchlp1203/mac

The article above should cover your attempt to change permissions on the folder in question. Based on your information, you might need an admin user to grant you admin status or just clean things if you can not.