I have been trying to figure out the reason behind smartscreen and I have read from microsoft's documentation (https://support.microsoft.com/en-us/topic/what-is-smartscreen-and-how-can-it-help-protect-me-1c9a874a-6826-be5e-45b1-67fa445a74c8) that smartscreen will appear when a downloaded file is from an untrusted web (that is not in the trusted list of microsoft) or when a downloaded file contains malicious software that has been reported to microsoft. I found out that if I download an .exe that was send through skype app, the smartscreen doesnt prompt but it does prompt when I download the .exe from skype web. However, when I download it from both Whatsapp app and web, the smartscreen was sure to prompt. So, I'm actually wondering what is the reason behind this?
It basically flags all .exe files after checking the source (e.g. if source is Adobe, it lets it go). If the app has been sent through the Skype app, the system assumes the file would have been checked on the system that sent it and thus flags it safe.