NMI said:
Unlike UAC? Doesn't UAC always require user interaction?
UAC can be programmatically responded to.

CTRL-ALT-DEL is the absolute certification a "physical"user is standing in front of the keyboard when it happens.

It is still required on any high security computer and is highly suggested in FIPS compliant networks.

From MS:
Microsoft developed this feature to make it easier for users with certain types of physical impairments to log on to device running the Windows operating system; however, not having to press the CTRL+ALT+DELETE key combination leaves users susceptible to attacks that attempt to intercept their passwords. Requiring CTRL+ALT+DELETE before users log on ensures that users are communicating by means of a trusted path when entering their passwords.

A malicious user might install malware that looks like the standard logon dialog box for the Windows operating system, and capture a user's password. The attacker can then log on to the compromised account with whatever level of user rights that user has.
MS admitting logon screen can be tempered here... And it can I can replace elements of it and windows does not notice.

Requiring CTRL+ALT+DELETE before users log on ensures that users are communicating by means of a trusted path when entering their passwords.
This is enough for me to require it "EVERYWHERE"

https://docs.microsoft.com/en-us/win...e-ctrl-alt-del