By definition, a loader modifies the Master Boot Record (MBR) or the boot manager. Malware developers love this because they do the same thing. When you run Windows Loader, you are giving a random piece of unsigned code rootkit-level access to your machine. Modern antivirus software (Microsoft Defender, Malwarebytes) flags these behaviors as "HackTool:Win32/AutoKMS" or "PUA:Win32/DazLoader."
No matter how nostalgic you feel about Windows 7, using Windows Loader 2.2.1 is software piracy. Microsoft’s licensing terms prohibit circumvention of activation. While Microsoft rarely sues individual home users for using a loader, they will: Windows Loader 2.2.1
For businesses, using a loader is catastrophic. Audits (conducted by BSA or Microsoft) will detect the mismatched SLIC, resulting in fines of up to $150,000 per unlicensed copy plus legal fees. By definition, a loader modifies the Master Boot
Between 2010 and 2018, Windows Loader 2.2.1 was ubiquitous. Why? For businesses, using a loader is catastrophic
For many users in developing nations, or students who couldn't afford a $100 license, Windows Loader 2.2.1 was the de facto installation method.