In other words, I think the goal is not just to add new developers to the community, but to continue to build a strong community of developers.
FWIW, from a Python community newbie that has submitted a few patches and commented on the tracker for a few months, I agree with this statement and the way things are now. I was attracted to the Python community, in part, because the development model seemed so mature and well specified. I felt that it was clear from the current documented policies on how I could contribute -- do these things and get these privileges. That simple.
Moreover, by having the different stages (do these things to get tracker privileges, do these other things to get commit privileges, etc...) it was more clear how I could set personal milestones for myself to become a contributing member of the community. I find these "stages" useful for the current community to somewhat gauge an unknown person's ability, but also for that unknown person to develop and learn about the community at a reasonable pace.
Yes, I know that the issue in question involves not a _completely_ unknown person, but someone who is known by an existing member of the community. However, this is about a community choice and not just one person's choice.
Not to mention the fact that most anyone could have already submitted the amount of comments needed to get enhanced tracker privileges in the amount of time that has been spent on this thread :-)