Closing as not a bug. It is working correctly. Try setting the text of a different Text object: it is running the event.
The problem is the OR block runs, and finds that no instances of the Text object have that instance variable value. However because the system condition was true, it runs the event anyway, but with zero Text objects picked. This means there are no instances to run the "set text" action on.
If the object's text was changed, it would mean an action ran on an object that did not meet the event's conditions, which contradicts the way events work.