Despite its age, CS2 introduced foundational tools still used in modern Photoshop: Smart Objects: Allows non-destructive scaling and transformations. Vanishing Point:

: Adobe has explicitly stated that CS2 was never intended to be free. The special version released previously was a workaround for legal owners after the original activation servers were shut down.

Portable apps do not receive security patches, leaving your system vulnerable to exploitation. Technical Compatibility Photoshop CS2 (is dead). - Adobe Community