There are a lot of unreviewed PRs, which is another reason for getting stuck.
I think just reviewing and approving current PRs is a dynamic way to speed up development.
I am sad that I do not understand C++ and many GitHub details, as well as my imperfect English. However, the community members are kind enough to understand my clumsiness in contributing, and there have been primitive changes that reflect my soft-coded modification. It is not fast, but it has been being developed!