Have y’all checked if you get any JS error when you load your application?
After initializing my application with Bootstrap I noticed that I was getting an error with the generated code in application.js that was attempting to import Bootstrap from the gem.
After removing the Bootstrap import Turbo began working as expected.
// application.js
// Configure your import map in config/importmap.rb. Read more: https://github.com/rails/importmap-rails
import "@hotwired/turbo-rails"
import "controllers"
// import * as bootstrap from "bootstrap"