The piano thing is basically nonsense, but you're in the right general area.

The copyright may have elapsed on the original composition, but a specific arrangement of a public domain composition may be entitled to copyright protection as a derivative work. For example, the song "Scarborough Fair" pre-dates the modern concept of copyright, but Simon & Garfunkel's performance of the song contains novel elements that are subject to copyright.

(see article 802.6) https://www.copyright.gov/comp3/chap800/ch800-performing-art...