This is a funny comment. I have family in Israel who say similar things (recently: "Why are you still wearing a mask? In Israel we just vaccinated everyone.") Connections work that way in Israel because everybody was in the military. The crossover between tech founders and IDF is therefore by definition close to 100%. In America there is far less crossover. The last time military service was a widespread shared experience in America was the end of WW2.
You can still build a big network with ex-military buddies. Those bonds tend to be stronger than the ones formed in a non-military (or similar group/experience) network.
But you are correct, the percentage of the US population in the military is about 2%, and the percentage of veterans is about 7%.
This is how it works in Israel.
If he is that good, he must have tons of connections just waiting to be refreshed and activated.
Wish you luck.