But there's no guarantee that system-ui is even a sans serif font. Why make that change?
Because they're really different? system-ui is the specific font the OS uses for its interface... San Francisco in macOS/iOS/iPad OS, Roboto in Android, Segoe UI in Windows, etc. sans-serif is often Arial or Helvetica, but could be anything.
Because they're really different? system-ui is the specific font the OS uses for its interface... San Francisco in macOS/iOS/iPad OS, Roboto in Android, Segoe UI in Windows, etc. sans-serif is often Arial or Helvetica, but could be anything.