Why does Sony care about RAP files for a dead console? Because the PS2 Classics emulator on PS3 is still proprietary software. The RAP file is technically a copyrighted cryptographic token.
The PS2 Classics Placeholder is a homebrew "launcher" that mimics an official PlayStation Store PS2 title. Because non-backwards compatible PS3 models (Slim and Super Slim) cannot play PS2 ISOs directly like a disc, developers created this tool to trick the system's built-in software emulator into running your custom game files. The Role of the RAP File Ps2 Classics Placeholder Rap File
If you are using HEN, follow this standard process to play PS2 games: Why does Sony care about RAP files for a dead console