In my city, they did traffic calming, mainly for around schools.

"Calming" isnt the right way to see it. It's just redirection, the fast drivers take a different path instead; but so do many other people who were never part of the problem.

But you know what happened? They redirected traffic away from businesses now dont stay in business for very long. Wrecking the local community run businesses.

Businesses that depend on fast-driving cars are near schools? Seems like another planning problem