We present the first large-scale comparative analysis of Truth Social and the most popular conservative Reddit communities, r/Conservative, r/conservatives, and r/Republican. Using topic modeling with FASTopic and LLM-assisted refinement, we analyze topic prevalence, toxicity, and temporal dynamics across these communities during the first eight months of Truth Social. We find clear contrasts: Truth Social centers on grievance and narrative-driven content, while Reddit focuses more on policy debates. Toxicity is higher on Reddit and peaks in cultural and leader-focused topics. Despite similar event-driven participation shocks across platforms, Truth Social shows higher baseline proportions of users engaging with political topics. Our findings contribute to understanding how alternative right-leaning platforms reshape online discourse.

翻译：我们首次对Truth Social与最受欢迎的保守派Reddit社区（r/Conservative、r/conservatives 和 r/Republican）进行了大规模比较分析。利用 FASTopic 主题建模及大语言模型辅助精炼技术，我们分析了 Truth Social 上线前八个月内上述社区的话题流行度、毒性及时间动态。研究发现显著差异：Truth Social 侧重于叙事驱动的愤懑表达，而 Reddit 更聚焦于政策辩论。Reddit 的毒性水平更高，且在文化及领袖相关话题上达到峰值。尽管各平台均出现相似的事件驱动型参与激增，但 Truth Social 中用户参与政治话题的基线比例更高。本研究有助于理解另类右翼平台如何重塑网络话语格局。