Qualcomm has published the results of a study conducted by Ookla on 5G speeds in the US and UK for the first and second quarters of 2020 (1-2Q2020). It apparently concludes that the fastest phones in this regard had chipsets and modems made by this prominent chipmaker. Specifically, they were the Snapdragon 865 and Snapdragon 855+ mobile platforms.
https://www.notebookcheck.net/A-new-Ookla-study-shows-Qualcomm-has-the-fastest-5G-chipsets-in-the-UK-and-US.484015.0.html