I recently did realtime collaborative editing of the same file with a Visual Studio Code plugin and have also often used Google Docs and its really not an issue

I recently did realtime collaborative editing of the same file with a Visual Studio Code plugin and have also often used Google Docs and its really not an issue in practice. If it were to suddenly stop me to notify me that there was a conflict, that would be a very jarring and unpleasant workflow. As josephg says, you don’t want merge conflicts in realtime editing and for offline editing, a git merge conflict resolution style is probably more appropriate.