Data is Beautiful

https://www.sciencedirect.com/science/article/pii/S0169204623002207

Its not entirely clear, but it can be seen that traffic is worse when you have 20 traffic lights for crossroads in a row... Or at least its logical. The cities that grew over time with circular planing have better capacity even on thinner roads, meanwhile grid cities have up to 8 lane roads (4 in 4 out) very often as their main road.

Its not 100% clear but its pretty likely that its one of the factors. Another one is public transport.