It's like a singularity of a black hole, where time seems normal to you while time flies outside.
Also because of the fact they'll probably won't be able to leave in the same time period anymore. Or literally that place if they can't use the stairs beside them.
It doesn't matter anymore. They're not going to be able to leave, since the elevator is now a relic of the past.
Looks like the shaft remains functional, and the elevator doors are ajar. As log as they are careful, climbing down may be an option. What I really wonder is if the area outside the corridor is affected- IE, if they climb down from their current position, is the world outside the apartment in accordance with when the complex was new, or when the elevator stopped functioning.
In a way, this hallway is the ultimate safe area. Since no monsters have appeared for the thousands of years that they've been standing there talking it's likely that they won't appear at all. They're effectively outliving everything and everyone in the complex.
This anomaly feels relatively benign, really. It doesn't kill you or make anything horrible happen to you, it's just... time. If you have no attachments and want to time travel, it could be useful, even- albeit the time machine here is one-way. You would basically need to crush a Jupiter sized mass down to relatively small dimensions otherwise if you wanted to do this kind of time travel IIRC.
It does nothing to you physically. The only harm done is to end your relationships with anyone who doesn't follow you down the hallway - if you go far enough, you will never see anyone you knew again.