> On macOS Catalina, Gatekeeper not only checks whether the software was signed by a valid Developer ID certificate, it also "phones home" to check whether Apple has notarized the software, again refusing to run it if the check fails.
Nit: I believe stapling is supposed to fix this issue.
> Nit: I believe stapling is supposed to fix this issue.
No, even stapled apps phone home. The difference is that stapled apps can still run if Catalina can't contact Apple (e.g., no internet), whereas unstapled apps can't.
Look closely at the Gatekeeper dialog with and without your internet connected.
Nit: I believe stapling is supposed to fix this issue.