Without getting into semantics of "vanilla", exuberant-ctags is listed as a dependency for [geany-plugin-ctags package](https://packages.ubuntu.com/focal/geany-plugin-ctags) on Ubuntu.
So it will be fetched automatically for anyone getting Geanyctags plugin . This is how exuberant-ctags found its way onto my box, that is specifically for geany-plugin-ctags. As long as these two are listed together, we need to make sure they can work properly together too.