Against the background of China’s rural revitalization strategy and the implementation of the “Thousand Enterprises Help Thousand Towns” initiative, the input of industrial resources from external enterprises has become an important driving force for rural industrial upgrading, yet the implementation effect of enterprise assistance varies sharply across different towns and villages. Existing literature mostly focuses on the direct promotion effect of enterprise investment while ignoring the heterogeneous absorption capacity brought by differences in rural comprehensive development level. Centered on the “environment-behavior-performance” theoretical framework, this study divides rural comprehensive development into four core dimensions—economic income, social governance, public cultural service, and ecological environment—and constructs a moderated PLS-SEM model to verify its conditional moderating effect on the path from enterprise assistance to industrial performance. Based on 170 valid survey samples from nine counties and districts of Zhaoqing City, empirical results show that rural comprehensive development exerts significant positive moderating influence: the marginal promotion coefficient of enterprise assistance on industrial performance reaches 0.53 in high-level developed rural areas, but drops to 0.21 in low-development villages; infrastructure construction and grassroots governance are the core threshold factors determining the moderating strength. This research supplements the theoretical system of enterprise-assisted rural development and provides differentiated classified policy suggestions for the government to realize precise enterprise-village matching under the “Thousand Enterprises Help Thousand Towns” policy.