According to the Hugo glossary, a section is:
A directory of content pages with an _index.md file. A section may contain subdirectories without _index.md files. An _index.md file is optional in top-level directories. […]
(emphasis mine)
According to the page on sections:
By default, all the first-level directories under
content/form their own sections (root sections ) provided they constitute Branch Bundles.
By definition, a branch bundle must have an _index.md file.
So it seems the first quote says that a top-level section under content/ doesn’t need an _index.md file, and therefore doesn’t need to be a branch bundle, but the second quote says that top-level directories under content/ need to be branch bundles in order to be considered sections.
This seems to be a contradiction. Am I misreading this?