You were right that the page is written for those that know what they are looking for, which is just fine. If you are getting started in DS/ML/etc and you have used numpy, pandas, etc. polars is useful in some cases. A simple one, it loads dataframes faster (from experience with a team I help) than pandas.

I haven't played enough to know all it's benefits, but yes it's the next logical step if you are in the space using the above mentioned libraries, it's something one will find.