WEBM, is it the default option of yt-dlp downloads?

[Linux for blind general discussion]

All Youtube videos are transcoded to multiple formats before they become 
available. I believe that even if the video is uploaded in a supported format 
and bitrate, it still goes through a transcoding process that will somewhat 
reduce the quality of the file. Webm is usually the best quality transcoded 
format, and it is a royalty-free, non-patented format, making it ideal in almost 
every way. You can change the downloaded format using yt-dlp, but there is no 
way to get the exact file that was originally uploaded, or even to find out what 
that original format and bitrate was unfortunately.
~Kyle