Solved
Tasker allows deleting tasks used in other tasks
Currently, Tasker prevents the deletion of tasks that are associated with profiles. If a task is not associated with any profile, but is used in one or more other tasks using the "Perform task" action, the user may mistakenly delete such a task and Tasker will not show warnings about the consequences this deletion. It is necessary that the user be warned if the task being deleted is used in other tasks. I believe that this is easy to implement, since even now, when renaming a task, the user is warned about the name change in links to this task, so, links between tasks are also tracked in the current version of Tasker.