One of the barriers for mobility in Detroit is culture. The Idea that Detroit is the motor city often comes up when people promote other modes. The streets are wide and the city is designed for cars to move quickly, completely disregarding those without access to cars for whatever reason. It makes simple things like crossing streets difficult for anyone and much more difficult for seniors, kids, and people with disabilities.
There's a lot of clear ignorance and inconsideration from drivers in the city and region to those who aren't in cars.
When bike lanes were being implemented (even on Michigan Ave) the idea that cyclists had rights to the street was not well received by many. People are used to flying up and down these major roads and even on the highways traveling often times as much as 20 miles above the speed limit. This makes talking about things like biking walking and using transit seen as less desirable.
People often talk like because of winters, Detroit can't and shouldn't invest in other modes whereas going to Toronto, New York City or DC, even with cold winters, people walk more, use transit more, and bike more.
Same with the scooters. although they're getting usage, many people see them as a nuisance. When in reality, they're a step toward figuring out micro transit in a city, where many neighborhoods like population and have large stretches of vacant lots/buildings. The idea that mobility is important for EVERYONE seems to be lost on people who have access to cars.
The idea of public transit is seen as a tool only for the poor and seniors and high school students. It's seen as a last resort and people would rather drive illegally (not having car insurance or even a valid license)
Culture shift is needed for mobility to truly be easier for all Detroiters including those in neighborhoods like Southwest and North Corktown.