Here's another video from another company trying to do this for passenger cars. They have change in BSFC graphs:
https://youtu.be/PCDDXtFmtVs?t=135
The active prechamber is good for increasing EGR dilution which explains the large low speed low load gains, while the passive prechamber is only good at increasing combustion speed (you see a small ~2% improvement at low load low speed, while it goes up to 4% by 4000rpm, and I imagine the gains would be even more impressive at say 7000rpm). On a car with a smaller engine that operates at a higher mean load, the passive prechamber would still yield some pretty good gains combined with increased compression ratio.