[Adobe]: claims headings fail to have appropriate nesting

[teepeemm]

Using the same input as #1304:

\DocumentMetadata{tagging=on,pdfstandard=ua-2}
\documentclass{ltx-talk}
\title{Title}
\begin{document}
\section{Section}
\begin{frame}
\frametitle{Frametitle}
content
\end{frame}
\end{document}

Adobe's accessibility checker claims that the headings fail to have "appropriate nesting". VeraPDF reports that the PDF is compliant with UA-2.
AdobeHeadingNesting.pdf