This study examines how ordinary citizens construct and circulate populist discourse through social media, comparing two cases of bottom-up populism: Canada’s Freedom Convoy and France’s Yellow Vests movement. Drawing on grounded theory and mixed-method content analysis of 4,725 Facebook threads, the study identifies three production strategies—labeling, linking, and critiquing—and three narrative styles—division, emotion, and drama—that structure grassroots populist communication. These strategies enable decentralized publics to articulate moral boundaries between “the people” and “the elite,” mobilize affective solidarity, and perform legitimacy in the absence of centralized leadership. Cross-national comparison reveals that while French discourse emphasizes confrontation and anger, Canadian discourse privileges gratitude and national pride, reflecting differences in protest culture and institutional context. Yet, both cases exhibit similar emotional intensification and retrotopian storytelling driven by algorithmic visibility, illustrating how digital participation can deplete the deliberative commons it relies on. Integrating Farrer’s “tragedy of the commons,” the study reframes bottom-up populism as both a communicative empowerment and a potential mechanism of discursive exhaustion in networked democracies.