rayiner's context for "urban renewal/the ISHS" is clearly in the US, and must not be misinterpreted as a world-wide basis for all urban highway projects, as you have done.
In the US, Robert Moses was one of the foremost leaders of the urban renewal project. "He was a leading proponent of the idea that the best way to eradicate the supposed slums where Black people lived was to build highways through them." , quoting https://www.history.com/news/interstate-highway-system-infra... , which then quotes Moses:
> “Our categorical imperative is action to clear the slums,” Moses said in a 1959 speech. “We can’t let minorities dictate that this century-old chore will be put off another generation or finally abandoned.” Moses, who was also the chairman of the New York City Slum Clearance Committee, said that the highway construction must “go right through cities and not around them.”
We can see how "urban renewal" is code for segregation in https://papers.ssrn.com/Sol3/Delivery.cfm/SSRN_ID3715149_cod...
> Shortly following the adoption of the Interstate Highway Act, however, highway builders began to drop the pretense of urban renewal and vocally embraced their racial agenda as thriving Black communities were destroyed and removed. In many states, highway builders went out of their way to avoid white homes and community institutions but also went out of their way to route the highway right through the heart of Black communities.95 With federal funding in hand, “[t]he bulldozer and the wrecker’s ball went to work” on Black America.96 The destruction of a Black community to make way for Interstate 95 in Miami, Florida, provides an example of how construction of the interstate highway system was used to actualize a racial agenda to destroy vibrant Black communities. ... The destruction of Overtown was the realization of a decades-
long campaign by white business leaders to remove Black residents and
claim that land to expand Miami’s central business district.
The history shows the city leaders had for decades wanted to push the Black population out of what was originally called 'Colored Town' and "the Federal Highway Act provided the opportunity Miami’s leaders needed to seize Overtown and push out Black residents" - while 90% of the costs were paid for by the federal government.
It then gives other examples, like in Birmingham, AL where Interstate 65 was built to physically separate white and black neighborhoods, and in Atlanta, GA where:
> “wherever the highway[ ] system could possibly serve a racial function, it was developed with that in mind also.”160 Indeed, white Atlanta residents regularly called on the mayor and city officials to use the highway system as a series of racial barriers.161 The City’s white leaders did not hide this purpose.
Are there non-racial reasons to justify urban highways? Sure! But in the US as https://digitalcommons.macalester.edu/cgi/viewcontent.cgi?ar... writes:
> Engineers and governments built the freeways through Black communities partially to reinforce the waning segregationist identity of much of the country and advance the interests of white residents and partially because the monetary value of the land was so low. The construction both symbolically and physically reinforced racist policy without explicitly calling it so. Urban renewal was a gateway for a new wave of structural racist policies and projects. ..
> This wasn’t to say there weren’t legitimate grounds for many urban renewal initiatives. ... However, to end there would disregard the immense racism interwoven into the planning process. While racial capitalism and neoliberalism informed suburbanization and urban redevelopment, specific ramifications of those manifested in the highway infrastructure development. To begin, the use of eminent domain by the government to seize the land for the highway to sit on was more than implicitly racial. Geographic areas, often called African-American cultural enterprise zones, were economically robust. Still, the government and planners saw the opposite, marking much of the land occupied by Black people as low value. It was relatively easy to deploy eminent domain on those properties because they could argue that the government could put the land to better use for the larger public good, and it wasn’t incredibly costly either. This resulted in the widespread displacement of people who were most often Black or Brown and of low socioeconomic status. Urban planners, engineers, and local governments explicitly warned about this in a conference convened by the Highway Research Board in 1958 when they said that members of those non-white and low-income communities were facing the “greatest potential injury” from the displacement caused by the Interstate Highway System. ...
> In 1969, Nashville civic officials deliberately curved I-40 to avoid a white community. Highway planners in Birmingham, Alabama, did the same thing when planning the path of Interstate 59. Consequently, entire communities were leveled; Saint Paul saw its Rondo neighborhood torn in half by the Interstate Highway System, L.A.’s Sugar Hill, Syracuse its 15th ward, and more, all facing the grim reality that was a new wave of segregation.