David Kimura PRO said over 2 years ago on Hotwire Turbo Replacing Rails UJS :
  Turbo is essentially the replacement for Turbolinks so changes will be coming in the future. We don't know what that quite looks like yet, but there will be changes coming. As time goes on, I don't know what will become of Rails UJS either. There's a lot of unknowns right now, but this episode was looking to help demystify some of the issues with creating a new Rails application without Webpacker and seeing how things work with Hotwire.