This isn't a problem where you can just copy and paste a deductively-proven-correct-for-all-inputs solution and be done. One way or another you're creating problems for existing users and existing scripts as soon as you start using the new location. A newly provisioned system with an old script (or an old user (and "old" meaning nothing more than "older than this change")) running on it is going to end up thinking that it's doing a create-or-modify on, say,`.bashrc`, when in fact it's doing an override (because existing config was in the new location).
"Ignorance" is being blind to that problem (and others). "Arrogance" is pretending like it's somehow obvious that that problem isn't worse than the benefits of unifying on this convention, especially when there are so many examples of estimable projects on both sides of the issue.