Repro steps:
Create an empty project witht he Lightweight template.
Wait for the project to load up
Notice the errors
Notice the Game screen is completely black

Errors pop up as well:
Shader error in 'LightweightPipeline/Standard (Simple Lighting)': failed to open source file: 'LWRP/ShaderLibrary/LightweightPassShadow.hlsl' at line 128 (on d3d11)

Compiling Vertex program with UNITY_PASS_SHADOWCASTER
Platform defines: UNITY_ENABLE_REFLECTION_BUFFERS UNITY_USE_DITHER_MASK_FOR_ALPHABLENDED_SHADOWS UNITY_PBS_USE_BRDF1 UNITY_SPECCUBE_BOX_PROJECTION UNITY_SPECCUBE_BLENDING UNITY_ENABLE_DETAIL_NORMALMAP SHADER_API_DESKTOP UNITY_LIGHT_PROBE_PROXY_VOLUME UNITY_LIGHTMAP_FULL_HDR

and:
Assertion failed: Assertion failed on expression: 'success'
UnityEditor.ShaderUtil:CreateShaderAsset(String)
ShaderGraphImporter:OnImportAsset(AssetImportContext) (at C:/ProgramData/Unity/cache/packages/packages.unity.com/com.unity.shadergraph@0.1.17/Editor/Importers/ShaderGraphImporter.cs:75)
UnityEditor.Experimental.AssetImporters.ScriptedImporter:GenerateAssetData(AssetImportContext)