I dont think you can download that type of data

Your best bet is to use the API, to get the raw data of runs in a certain leaderboard (in JSON format), and then move that to Excel.

This post was copied from reddit.

Does anyone know if it’s possible to download speedrun leaderboards to an Excel spreadsheet? I’m trying to run some very basic data analysis on some of the more popular runs and I don’t want to have to manually put in hundreds or thousands of times