This study examines the genre of YouTube reaction videos as a distinct form of cultural production and social influence in online communication. Despite its prevalence and popularity, the genre has received limited scholarly attention, particularly with regard to reactions to ideological activism. This paper aims to fill this gap by conducting a social semiotic discourse analysis of videos reviewing the activism of transgender community on TikTok. The analysis demonstrates how intersecting non-verbal and technologically enabled modes, such as gaze, gestures, facial expressions, and various audio-visual effects, contribute to the expression of impoliteness arising from a sense of superiority over the target, shared with non-targeted viewers. Overall, the paper provides insights into the dynamics of online culture wars and the multimodal manifestations of impoliteness in contemporary social media discourse.