https://phabricator.wikimedia.org/project/profile/38/ states that This project [...] stopped around May 2015.
https://www.mediawiki.org/wiki/WMF_product_development_process is still marked as a draft and has not seen updates since 2016.
If this is not an active project anymore, then it should be archived and its open tasks cleaned up.
If this is an active project then it would be great to edit the project description to explain which WMF team is resonsible for this (or provide pointers who to ask instead...). Thanks in advance! :)