It is my fault that python developers were not contacted. I added the package to dla-needed.txt yesterday (or possibly the day before) and planned to contact the maintainers. But before I had the chance to do so the package was already fixed and then it did not feel appropriate to contact the maintainer. I should have sent the email the same day and not wait until another day.
On the other hand, we have mixed feedback from maintainers.
Some wants to be contacted.
Some other do not want to be contacted.
Some other want to be contacted, but just the people in "Maintainers:" field and not the "Uploaders:". (This turned out to be a rather tricky thing)
I think I agree with you that we should change the process, but we should discuss it first as you say.