The short answer is yes. The almost as short one is "Conda has it already, use that". The slightly longer answer is that I don't think that this is the right thing for Debian to do. We are then shipping an old version of matplotlib, i.e. oldstable, with a new release of our distribution. I do also think that that long-term support version 2 of matplotlib should remain in our distribution. So we would need to find a way to support two versions for the same distribution.Let me ask you this: where is the rush to package this machine learning library? Could it wait after the Buster release cycle, where we might be in a more comfortable position to upgrade matplotlib?
Kind of answering myself - I do not see a rush, either. I was just positively surprised about Orange and would like many users to share that experience with Buster - not two years later.
How deep is the Python Policy wrt package naming set in stone? Wrt to the renaming that Andreas suggested - I would be prepared to work through renames of matlibtools to matlibtools2 in all those source trees that are incompatible with version 3.
Cheers, Steffen