Wdym? This is the door of the coach itself. Of course it has door. But it didn’t have doors for individual coupe like 1AC. Even 3 AC has the coach door. Curtains were removed from 2AC and 3AC by IR showing various reasons. Edit : Ah I see what you mean, the last part of the video. No, that was not the norm in 1990s at least. That may be a one of a kind special coach. Probably it was a former first class or 1 AC compartment converted to 2AC by IR