There is no style applied for the [`versionremoved` directive](https://www.sphinx-doc.org/en/master/usage/restructuredtext/directives.html#describing-changes-between-versions). It was added in Sphinx 7.3.  I would suggest using the same color as [`deprecated`](https://pydata-sphinx-theme.readthedocs.io/en/stable/examples/kitchen-sink/admonitions.html#deprecated). A removal feels as severe, if not more than, a deprecation. I'd be happy to submit a pull request with whatever color you think is best.