> XDG Base Directory Specification has been a standard for organizing application data files under Linux for a long time. Unfortunately, wxWidgets has been around for even longer, and when support for configuration files was added to it back in 1997, the usual convention was still to put these so-called “dot files” directly in the user home directory

Who do they think defined this standard, if not the people who had "been around even longer".

IIRC KDE was first with cleaning up the clutter by hiding things in ~/.kde or something like that, but there's a ton of config/bookmarks/menus/data/caches you want to everything to use, so it was a given that there would be some standardization.