“Many antivirus software incorrectly flag a Delphi generated EXE as malware. So they are false positives.”
The KeyGen modifies the XML file, embedding a valid cryptographic signature that fools the software into recognizing the PC as a legally licensed machine.
That said, the community’s rationale—right or wrong—often revolves around the exorbitant cost of genuine licenses and the fact that many users are hobbyists or small independent workshops operating on thin margins. The keygen provides a way to access powerful diagnostic capabilities that would otherwise be out of reach.