On core dev bottleneck there were 10.5k PRs merged across different branches since GitHub transition with 4k PRs made by three core devs including miss-islington (2k PRs). So around 40% of PRs were created with three accounts. The number of open PRs is also keep creeping up that I guess there were 750+ open PRs by September 2018 and the count might be 1000 in few weeks with currently 990+ open. This might cause bus factor problems especially with most of the development unpaid and on volunteer time when people move on to different endeavors. There is also no major company backing up the development directly with respect to finance like Go, Java, C# etc. to hire new developers to take care of development and so on.
As a personal experience moving to GitHub with automation saves a lot of time, reduce workflow related bottlenecks and can attract new contributors. Like for a doc fix I can edit it on GitHub with a fork and make a PR where previous setup required a patch to be uploaded. But with a project like CPython that is highly stable the number of low hanging fruits to work on is also less. Some people might find that after a few months due to lack of motivation on trying out other areas due to lack of platform specific knowledge, less C experience etc. to move on to other stuff once they make an initial set of improvments. So there could be potential candidates who were highly motivated initially about the project that might be missed out on converting them to long term contributors due to lack of feedback, mentorship, direction etc. So this adds another set of tasks to the core team in addition to their own tasks at hand during volunteer time. I am sure these have been discussed a lot across different timelines but without full-time devs I hope there is a long term plan while dealing with new contributors and old contributors cycle so that people enjoy contributing with less entitlement on contributor and core dev part.
I would also recommend “The hard parts of open source” by Evan Czaplicki, creator of Elm https://youtu.be/o_4EX4dPppA
Edit : It’s a known problem even with large open source projects even with a company/foundation behind it.
- Two rust core devs left Mozilla last month and there were talks about an independent foundation to drive development and finance.
- Clojure receives periodic attention about software entitlement around process and core team at Cognitect who steward most of the development.
- Perl6 uses grants for development and new features.