Under-the-Hood Security Improvements
In addition to Activation Lock and the new Find My feature, macOS Catalina also has a slew of much more hidden security-related features. And while they may be relatively small and unexciting changes, they could go a long way toward making your Mac secure.
For one, the System Volume is now in its own read-only partition — meaning only approved Apple code can make changes to it. There are also several improvements to both the built-in macOS Gatekeeper and app access requests. Those two features could help protect your device from malicious software.