Typically software signatures are not just pass/fail, but used to give audited entitlements for API. So a secure system would let you run Doom, but could forbi

Typically software signatures are not just pass/fail, but used to give audited entitlements for API. So a secure system would let you run Doom, but could forbid:' - Access to the filesystem outside the application domain due to potential for exfiltrating or destroying user data - Likewise, access to global system data may be limited - Access to the network due to (raw TCP/UDP) traffic not having been audited for security, and the network connectivity being usable for exfiltration - Access to run full-screen due to the ability to perform user phishing attacks by presenting fake UI. - The ability to disable system-registered keyboard sequences (on windows, such as the windows key or sticky keys) - Access to mouse events outside its window - Access to key scan data, although this likely will be emulated - Access to change display color modes to e.g. 256 color indexed, although this will likely be emulated as well