@noleli@brucelawson@aardrian it looks like the primary problem is with section +expecting a document outline algo that doesn’t exist, not with <section> as a container in combo with properly-nested h1/2/3, except in so far as section may not have a purpose without said algo?
ISTM that your proposed use is closer to the container w/ proper header tags when applicable. Another option could be “<h3 class=untitle>Untitled Section</h3>