The emergence of text-to-image generative artificial intelligence (GenAI) is revolutionizing the creative industry by providing the capability to produce visually appealing artwork using natural language prompts. This study examines the impact of GenAI on creative professionals, using firsthand data to scrutinize their responses and strategies for mitigating perceived threats that obstruct the integration of GenAI into their professional practices. Our extensive investigation, which includes an exploratory interview study (n=79), an experimental study (n=197), and a two-wave longitudinal survey (n=119), reveals that firsthand experience with GenAI significantly enhances creative workers’ understanding of its technical features, including aesthetic appeal and functionality. This enhanced understanding, in turn, motivates them to adaptively incorporate GenAI into their creative workflows, thereby reducing the perception of GenAI as a threat. By adopting a mixed-methods approach, the study not only highlights the challenges posed by perceived threats to the effective utilization of GenAI but also emphasizes the effectiveness of firsthand experience as a strategy to overcome these barriers.