Corrupt download or conflicting mods. Fix: Delete the update from System Settings → Data Management → Delete Software Update. Then re-download. On emulators, remove all mods, then add them back one by one.
On Switch, 1.6.0 enabled proper cloud saves for BOTW via Nintendo Switch Online. Previously, the game would sometimes fail to sync correctly. This update fixed the handshake between the game and Nintendo’s servers. botw update 160 work