Case: 1383963, Unity 2022.1.0a15 & URP13.1 or built-in RP
Create a new project (for example URP 3D template), switch the platform to Android, and boom - the shadows are jagged no matter if “Soft Shadows” are checked/unchecked in the URP asset (first picture - when Windows/Mac/Linux platform is selected, second picture when Android is selected)
After a bit more of research, I see that built-in suffers from the same problem too. It feels like built-in RP tries to blur the shadows, but not enough. When the Windows/Mac/Linux platform is selected everything is fine again Pictures