When creating a new Blazor sample (dotnet new blazorwasm) and publishing in release, the linked corelib appears to still have lots of entries in System.Runtime.Intrinsics.*, which are kept around because of a call to System.Runtime.Intrinsics.Vector128. This appears to be used in Utf8Utility.GetPointerToFirstInvalidByte, but is guarded behind a call to AdvSimd.Arm64.IsSupported and ought to be linked out.