Buffalo tried this a few decades ago and it did NOT work. The entire area died, all the restaurants & retail closed. It took millions of dollars and many years to undo it and now the area is back and full of people. I don't know for sure the blame lies entirely on the clearing of cars idea, but that sure didn't help. The city (like many) fell pretty hard for a bunch of reasons at the time they tried this.
https://www.buffalony.gov/1054/Cars-Sharing-Main-Street