I also think the common framing as freeways "cutting a path through neighborhoods" is exactly the wrong way to look at it. San Francisco's, for example, were based on this 1935 traffic study. The whole point was to get already-existing traffic up off the streets and keep neighborhoods livable: https://www.flickr.com/photos/walkingsf/5409261018/in/album-...
There's (unfortunately) a real-world example I can point to showing this still holds up in the 21st Century. The northernmost part of the Central Freeway carried more than 50% crosstown (non-neighborhood) traffic in San Francisco but was torn down in the very early 2000s and replaced with the horrible Octavia Blvd that keeps killing cyclists and has made neighborhood traffic worse in every way, even necessitating crosswalk closures. Here's the full study on before and after the "Freeway Removal" (now there's a dogwhistle for ya!) https://www.sfcta.org/sites/default/files/2019-03/Final%20Re...
"In the absence of meaningful improvements to travel improvements, the reduction in automobile capacity has not been accompanied by noticeable mode shift. Instead, the neighborhood has been challenged to effectively deal with high peak‐period traffic levels and resulting congestion"