Are you sure? Wikipedia article does say at the top "This article needs to be updated
. Please update this article to reflect recent events or newly available information. (January 2021)"
Apple's documentation is pretty silent on the name Aqua. The only reference I can find in the Human Interface Guidelines lists the default system colours used in 'Aqua' and 'Dark'. https://developer.apple.com/design/human-interface-guidelines/macos/visual-design/color/
Suggests to me that Aqua if it has any meaning is only as Light Mode. I am happy to be shown some other current Apple references to Aqua.