> In Seattle is running 4 car trains at 8 minute headways at peak which works out to 7500 people per hour at crush load (4 cars, 250 people per car, 7.5 times per hour). This would require 125 vehicles with 5 seats leaving every minute which is clearly impossible.

7500 isn't that high - the Manchester Metrolink did 46M user journeys in year ending March 2025 (~5250/hour assuming 24/7 which it isn't.) Docklands Light Railway did 97.8M (~11000/hour ass.24/7)

Numbers from https://www.gov.uk/government/statistical-data-sets/light-ra...