Microsoft’s own dism tool can compress Windows image files ( .wim or .esd ) using high-ratio algorithms:
Windows 8 may be out of mainstream support, but in its highly compressed form, it remains a nimble, speedy ghost of Microsoft's past—perfect for those who know exactly what they are doing. windows 8 highly compressed
The most effective way to "generate" a highly compressed Windows 8 version is to strip it down before installation. The Rise and Fall of Windows 8: A
While "highly compressed" versions can be a fun experiment for tech enthusiasts on air-gapped, legacy machines, they are for daily use. If you need a lightweight OS for an old computer, modern Linux distributions (like Lubuntu or Linux Lite) are safer, more stable, and legally free alternatives. and legally free alternatives. Conclusion