I may be able to explain.
This forum ("Help Each Other") is NOT locked. All points of view are welcome.
But there is a grammar forum that is locked. People ask questions, and then they get an answer from Alan. Many students of English want an informed answer. So Alan gives them an informed answer. If that forum were open, then many people (such as I) would answer. Maybe my answer would not be informed. Then the person who asked the question would be confused. By locking that particular forum, there is no confusion.