The help article Lightroom Classic GPU FAQ should mention Export in the introductory summary paragraph, since that's likely to be one of the most-noticed uses of the GPU. The article has plenty of details down below, but when looking for an article to refer to a forum user, I almost moved on since I didn't see Export mention in the introduction:
"When configured (Preferences > Performance), Lightroom Classic can use a compatible graphics processor (also called a graphics card, video card, or GPU) to speed up tasks of displaying and adjusting images in the Develop module, the Library module's Grid view, Loupe view, and Filmstrip. Features like Select Subject, Select Sky, and Enhance Details are also accelerated by the GPU. Using a compatible GPU can provide significant speed improvements on high-resolution displays, such as 4K and 5K monitors."