How exactly did it break your workflow? The change only affects new repositories and doesn't prevent you from creating a master branch on those new repositories. You're even able to set any branch name as default on a user, org, or enterprise level.
If someones existing repo changed their own branch name then it was the decision of that repo owner.. not related to anything GitHub did - technically if you see what's happening, Github barely did anything for this change..
I don't really care; I fixed the scripts. The question was if there was any impact, and not if the impact was onerous.