I heard a performance last night of a violinist who plays in a string quartet performing a Beethoven Sonata for Piano and Violin together with a talented undergraduate as part of a project to teach students the repertoire by playing together with them.
When the priority of these works is reversed so that they become Sonatas for Violin and Piano the role of the pianist is reduced to that of wallpaper or floor covering. It should rather be that the sound of the piano pulls into itself the sound of the obbligato instrument. This is what a well-managed damper pedal accomplishes if both players know how to listen.
Without listening and without proper use of the pedal the piano timbre drives the pitch of the violin higher and higher. Is this what Beethoven had in mind?