Beyond the Platform: A Comparative Analysis of How Consumer Characteristics and Valuation of Brand Attributes Moderate the Drivers of Consumer Behaviour on Facebook, TikTok, Instagram, and LinkedIn

In today’s fragmented digital landscape, a one-size-fits-all approach to social media marketing is ineffective, as platform-specific conditions critically shape consumer responses. This study moves beyond general examinations of social media’s impact to provide a comparative analysis of how consumer characteristics moderate behaviour across four major platforms. Using survey data from 435 Sri Lankan social media users—368 on Facebook, 103 on TikTok, 187 on Instagram, and 194 on LinkedIn—moderation analyses were conducted with the PROCESS macro for SPSS (Model 1). The results highlight clear and theoretically significant contrasts. On mature platforms such as Facebook and LinkedIn, age emerged as a dominant direct predictor of consumer behaviour, while on Instagram it functioned as a moderator, amplifying the role of personal interests and brand characteristics among older users. In contrast, age was negligible on TikTok, where spending played a more powerful role, uniquely moderating interactions with “heavy user” status and psychosocial cues. Similar spending-based activation effects were observed on Instagram but absent on Facebook and LinkedIn, underscoring platform-contingent consumer psychology. These findings carry important managerial implications: Facebook and LinkedIn demand age-based segmentation, Instagram strategies should target older users with interest-driven and brand-focused content, while TikTok strategies should prioritize commercial intent over demographics, with emphasis on high-spending segments. Tests including Social Media Platform Characteristics indicated no age-contingent effects across platforms and a marginal, age-invariant association on LinkedIn. The study cautions against directly porting strategies across platforms and contributes by empirically demonstrating that psychological mechanisms of influence are not universal but shaped by each platform’s structural purpose and user dynamics. This study advances a platform contingency perspective , offering a nuanced model for effective platform-specific marketing strategies.