When you see sites offering "Highly Compressed PC" versions, they are typically providing one of two things:

: This allows you to play the Xbox 360 version of the game. While functional, the 360 version has lower graphical fidelity and fewer features compared to the Xbox One version.

: Microsoft delisted Forza Horizon 2 from the Xbox Store in 2018, and online servers were shut down in August 2023. It is not available on Steam or the Microsoft Store. Risks of "Compressed" Downloads