Shameless plug: I am the author.
Are there other relevant standards? The XDG base directory specification has been around for a long time, and is well established.
Maybe your comment wooshed over my head; if so I apologize.
Well, when software supports this standard, you as a user have a way to not confirm to it by setting the env variables to whatever you want, even per app. So you have two choises, either use it as is or change it.
But if software doesn’t supportthe spec, there is no choise of using it. So ons choise less.
This standard makes your software’s paths user-configurable, giving users a choice.
And if I don’t agree with how that standard is implemented? I should have the choice to use something else. Isn’t that how everything works?
To conform to a standard or do something else are each a choice. If you can justify your choice then perhaps it’s a good one.