I'm currently working on a solution that will try to quantify software development health, and what I've learned from analyzing thousands of popular open source projects, is you don't want a single individual to stand out. You want work to be fairly distributed to reduce knowledge risk.
If you look at the busfactor section for the vscode and gitlab repository
https://imgur.com/NfgvvTy (vscode)
https://imgur.com/DK7rvfx (gitlab)
You'll find they both have a large cluster of developers in zone 2. For developers to exist in zone 2, they have to have medium to high impact on the code that they worked on, but not clash with others. If you look at the vuejs-next repository
https://imgur.com/eDAOyPW (vuejs)
You can see it's actually a pretty fragile project, since Evan is responsible for pretty much everything.
Based on what I've observed by studying successful open source projects, you actually want to discourage "very high impact" employees, since they introduce knowledge risk.
Edit: The metrics that I'm showing is limited to the last 90 days for Typescript, Javascript and CSS code.