(My message below is not specific to Paul nor Joannah, I just took this thread as an opportunity to share my point of view ;-))
Thanks Paul for being honest and sharing your opinion 
Two years ago, I considered that contributors must be very productive in term of merged changes and on the tracker, and maybe also on the mailing list, to be promoted.
I changed my mind. In short, I consider that as soon as someone does anything useful to contribute to Python, this person deserves to become a core developer (in the long term, âwhenâ depends on the commitment and my estimated value of these contributions). It doesnât have to be code. It can be review, bug triage, useful comments on the bug tracker, mailing list, etc. It can mean helping other contributors to contribute (explain the workflow or whatever). People contribute in very different ways.
For example, Joannah wrote articles to give her feedback on contributing to Python. How to find things to do. How her work is reviewed. Other core devs rarely write such articles, whereas these articles are very valuable (IMHO) to help and motivate other contributors to contribute to CPython. The fact that these articles are not part of the devguide or related to a PSF blog doesnât matter to me. Publishing articles elsewhere gives more freedom how to write the article, and include a more personal feedback.
People who are contributing for a long time to Python donât write such documentation anymore, so we need more diversity in term of experience in Python: new contributors are more able to detect which parts of Python workflow are not well documented, and they like to share their experience.
Obviously, my intent is to get a snowball effect: more documentation and more mentoring lead to more contributors who write more documentation and help more people 
Contributors naturally help each others.
I consider that we need more people and we cannot afford to be picky on the minimum set of skills.
Well, I know that some other core devs disagree with me on that. And thatâs fine. The vote is here to record disagreement and discuss the criterias.
It seems that each core dev has different expectation, and the candidate must have all these combined expectations, which will never happen.
Contributors are usually motivated for 1 year and then move on to another shiny project (or just stop contributing to Python). We have to keep them motivated by giving them more responsibilities which is a way to say them: your contributions are valuable.
If we miss that, we loose contributors and we will only get simple changes from newcomers. Reducing Python technical debt requires more experienced developers.
Technical skills are less important to me than the ability to collaborate, be trusted by others, taking reviews in account (donât ignore other core devs on purpose), etc.
Reminder: we donât pay developer, so we have to be extra kind with people giving their time to Python!
In my experience, most contributors donât do review. Core developers feel more responsible for reviews and so are more active in that area. My theory is that contributors consider that their opinion doesnât matter. And some core dev confirmed that recently. In my case, I like to see reviews from contributors, it makes me more confident to merge a change. I donât feel anymore as the only one to be responsible for any future regression
Contributors tend to think that the only metric to become a core dev is to get merged commits and so they only focus on that. Well, most core dev think like that, so itâs a good stategy to become a core dev