You don't have to use it as a measure of productivity. I find running these kinds of stats on my code bases fascinating. This tool looks really neat imho, great work OP.
What I've found is this is well understood by technical people, but not so much by non-technical people.
I won't go into too much detail, but to make the long story short, Amazon, Google, Apple, and other tech giants are scaring the shit out of non-traditional tech companies in the financial industry, health care, etc. And the reason for that is, they (tech giants) are going into different verticals and they (non tech companies) realize they need to develop software faster and they are desperately looking for ways to help them overcome their ability to manage and attract tech talent.
So for them, when they see GitPrime, GitHub Insights and other similar solutions, they get very excited as they believe they found that magical translator that can help them better manage developers. This is why software metrics is rarely adopted by tech companies but is in high demand by non tech companies, which there are MANY. For example, I was talking to a developer in a food storage company that develops in-house software to manage their automation systems. It is these non-traditional tech companies that really want to be able quantify developer productivity and why lines of code, commits, can be so dangerous.
When I took time off from my first startup (which is the foundation for my current startup), I ended up working for a fintech with close to 1 trillion dollars in assets and my job was to help them transform into a technology company. And they were literally rewarding people (gave them gift certificates) for having the most commits, without even asking what the commits were for. Note, the company that I was working for wasn't the only large institution that is afraid of tech giants like Amazon and others.
Also Pluralsight paying 180M for GitPrime and GitHub paying a decent amount for Gitalytics signals that there is demand for software metrics.
GitHub Insights has turned into a hot topic for GitHub internally and if you use wayback to look at GitHub's enterprise sales page from a year and a half ago when they acquired Gitalytics to today, you will find they are pretty much sweeping GitHub Insights under the rug because they know how developers feel about software metrics.
Software metrics can (which is what I am working on) be useful for everybody, but right now, too many non-technical managers just want to "tell if an employee is dicking around or not". Until these non traditional tech companies lose talent, they will assume everything is okay. And based on what I've seen with the fintech that I worked for, many employees will just accept things, since it's not like Apple, Google, Facebook and others will fight for them.
The only way to better manage developers is to have a manager that used to be developer.
If that's impossible, the best option left would be to just trust the developers on their reports.
All of the other options that are taken (which I would say, for these traditional companies, 99% of the time) inevitably result in a mess.