Edge Canary limited disk usage capability on YouTube video upload

looks like the limit only applies to YouTube when it tells the browser to check the video file so it can know where it should restart the upload from. i can't test the same thing on the preinstalled Edge since it's a painful process but i did test both of them by drag and dropping the video file on the browser and then selecting "save video file" so it started download it (actually copying the file from one drive to another) and the speed went over 300 MB/s (Megabyte not megabit)
I use Windows defender.