Headphones can recreate the perception of auditory events localized inside or outside the head because signals are filtered by directional cues such as the pinnae, commonly modeled through head-related transfer functions (HRTFs).
The claim is a specific, empirically testable statement in psychoacoustics regarding how pinna cues shape spatial perception over headphones. The retrieved papers consistently discuss how spectral pinna cues and HRTFs govern spatial hearing and headphone-based localization, supporting the claim without any contradictory evidence.