There are very few chain grocery stores, drug stores, etc. in Detroit. There is a Whole Foods down Woodward avenue, near where the city is being rebuilt. Many of the local small mom and pop grocery stores have large pylons preventing you from taking the shopping carts away. All of the buildings have large iron bars on the windows.
You can always say "the rich company/people have insurance, so what", but that's missing the point. The point is, the economic core of the city largely left when they got fed up with the unrest, the lack of safety, etc. They left for and built up the suburbs around the city.
Now, the city leaders have been working with local investors (Illich and other groups) to turn desolation back into a productive tax base. To attract people to live and work there.
From what my wife (Detroit/Michigan native) tells me (escapee from NY), they moved out after the riots/unrest in 1967.
Cities get hollowed out when you can't guarantee safety. Businesses leave. Families leave. Your economic base flows elsewhere.
The folks at UP (my FIL/BIL worked there for many years) have a reasonable request of LA. Please make it safe for us to do business. The DA of LA appears to be following some other agenda, atypical of what one might expect of a DA. The end result will be (and likely is now), that LA will start slowly bleeding out as businesses and people come to the realization that their interests and concerns are not being addressed by local government.
In the case of Detroit, this hollowing out had another side effect, the effective capture of the political class by corrupt pols and other criminals. It took, arguably, 45 years, before they elected someone who actually worked for the people, and wasn't feathering their own nest. Many city council members leave by going to prison, only recently has that trend changed.
If you want that outcome for your city, have extreme unrest, coupled with lawlessness, an inability to pursue and prosecute criminals. You provide pressure for businesses to give up on you, as they did in Detroit. People leave when their small businesses move. Large companies close up shop and don't return.
I arrived here slightly after the nadir. I love Detroit, the architecture is amazing, the people resilient, the attitude ... one of never giving up. Detroit versus everyone.
But the pain that they went through to get there.
Take them as an object lesson, of the combination of ethical corruption, failed government, and criminal capture. You don't want to experience this. You really, really don't.