For all contributors who are struggling, here is my thought, hope it help !
TensorFlow are huge, doing a PR for Tensorflow takes a lot of time and effort. Things like
feedback/copybaraand internal stuffs make TensorFlow not really friendly for external contributors. However, TensorFlow still has 93 other repositories ! Many repositories ( e.g https://github.com/tensorflow/io ) are fully external and their codebase are much smaller compared to TensorFlow. Contributions to these repositories are still counted as contributions to TensorFlow. Many GSoC projects in the past years were mainly targeted these repos.
Just discover a bit more and you will find !