Notarization is required by default in macOS 10.15

[Bogdan Szabo]

Hey! Are you aware about this new change for macOS? I noticed 
that none of the mac installers are signed with apple 
certificates,which might be a problem in the future.

Beginning in macOS 10.14.5, all new or updated kernel extensions 
and all software from developers new to distributing with 
Developer ID must be notarized in order to run. Beginning in 
macOS 10.15, notarization is required by default for all software.

https://developer.apple.com/documentation/security/notarizing_your_app_before_distribution