Still occurs in iOS 14 GM seed. My bug report FB8626851 stills says "Recent Similar Reports: None".

This issue still occurs in yesterday's iOS 14 beta 7. Worse still, localized apps display the base-language custom message from the info.plist under a localized title and with localized action buttons, and thus ensure complete confusion for end users. I prefer now not to customize it and leave users with the misleading but pre-localized default description, which at least they can try to understand in their own language. I filed a bug report but have little hope that any human will ever read it.

This issue seems to apply only to simulators. iOS 14 beta 5 on a real device receives products as expected. Simulator support for IAP has always been weak. Product requests do still work on iOS 13 simulators, but not on iOS 14 simulators in Xcode 12 beta 5. You'll need a beta installation on a real device to test IAPs properly.