They are open. As can be seen by the fact tickets are being sold and bought. They have also been hit hard by covid. Why employ a team in a ticket office that could, at any moment, become inactive because the pandemic has taken a turn for the worse?
The majority of people have been buying tickets online/remotely for years anyway. It's only Mr and Mrs Triceratops of 4 Bedrock Avenue who need to do this physically and in person.
It's the way things are heading. It's a cheaper and more effective way to handle things. It is completely crazy to employ people who are sat doing very little for all bar the odd big game.