Command line arguments do not apply to the UProjectNameEditor.Target.cs.

1. Add to ProjectNameEditor.Target.cs:

public class ProjectNameEditorTarget : TargetRules {
	[CommandLine("-UnoptimizedCode")]
	public bool bUnoptimizedCode { get; set; }

	public ProjectNameEditorTarget(TargetInfo Target) : base(Target) {
		Console.WriteLine(bUnoptimizedCode);
..

1. Run PowerShell and enter: ../Automation/RunTest.ps1 -UProjectName "ProjectName" -UEngineDir "../Epic Games/UE_5.4" -BuildFlags "-Platform=Win64, -ClientConfig=Development, -Build, -Cook, -ubtargs=`"-UnoptimizedCode`""
2. The console will print: False.