The case against the series is strong: by 1955, before any Interstate was built, about seventy percent of America's postwar transit collapse had already happened. The reply is not that Americans should not have bought cars but that peer countries built highways and kept funded transit. The ratchet funds one mode automatically and the other by annual permission.
The ridership percentages and motorway-per-head ratios are arithmetic on published series, and the 1946 peak was war-inflated. No harmonized international public transport funding dataset exists, so the peer comparison is incomplete by admission.