It was not developed in a bubble. There was already a close relationship between the VIPM team and NI. So they knew the requirements and the need. It's been over 5 years since the release of NIPM, so not much movement however...
That might have been the first step, but hardly the long-term plan. In reality, I think the main reason for lack of development on NIPM is that people got shuffled around and new management came in and the original development plans for NIPM got put on a shelf. I can tell you that NI had the goal of full VIPM replacement.
There is much churn internally at NI on where to take NIPM next. They are back to wanting to add features to facilitate better reuse library installation for current LabVIEW (how to achieve this is not clear). For sure however, this is the clear case with NXG.
I suggest you watch this video: