Apparently others are frustrated with the lack of seating in the new hall. The pictures in this article were taken when I was there. I can barely make out my wife in one of the photos.
https://patch.com/new-york/midtown-nyc/seat-free-moynihan-train-hall-ridiculed-riders-slump-floor
It's a legitimate problem. Truly a shame no one thought of this with before.
South Station (though way more of a commuter station) also has similar problems.
Closing the train hall each night prevents it from becoming a true homeless shelter. There are also ways to design seats that make them pretty much impossible to sleep on.
It's a tough situation, for sure.
Is it able to stay closed for long? 66 doesn't depart until close to 3am, and 67 3:20am. And the first train out is only a few hours away after that.