The resources aren't "code" but people and time. You have a limited set of folks who consistently contribute and become reviewers/committers. This is all based on volunteer time - no one is paying these folks to do it. So, asking these folks to divide their limited volunteered time between multiple versions of python is unfair. I think this is the right decision to take.
If you feel you have "plenty of resources" you can fork the python2 version of numpy and maintain it.
If you feel you have "plenty of resources" you can fork the python2 version of numpy and maintain it.