The tutorials in tutorials/sample-datasets should be moved into other tutorial categories that better reflect what those sample data tutorials are actually doing / showing. E.g., polysomnography should go in a "clinical" category. Others might sensibly go under "preprocessing" or "time-frequency".

The docs page that summarizes / describes all our sample datasets can have links to tutorials in which that dataset is used, so that page will still be a one-stop place to see what sample data tutorials we have.