7 Reasons Not to Install macOS Catalina & 14 Reasons to Install macOS 10.15.7 Today

For Better Security And Privacy

Apple tightens up macOS security in macOS Catalina with a variety of changes. Apps will need to ask for access to files, similar to on the iPhone or iPad. 

The OS runs in a read-only volume that is on a different part of the drive then your data. This helps keep your files safe. Combined with GateKeeper it can prevent security issues. If you have newer hardware the T2 chip is even more powerful and integrates with your Apple Watch in new ways. 

At this point most macOS apps are updated to handle these changes, so you can get the full benefits of the update and of the app updates.