The main contribution of a technical leader is calling bullshit on things that are bullshit. Left to their own devices, large teams of people will produce a lot

The main contribution of a technical leader is calling bullshit on things that are bullshit. Left to their own devices, large teams of people will produce a lot of things, but someone qualified needs to decide which of those things actually need to be produced, and how to make them work when you put them together. So while you are right, and he is not the only person "behind Zen", it would also be wise to not underestimate how crucial his contribution was. Dude very obviously knows his shit.