In "Friends", Season 5 episode 5 (1998), Chandler tells Joey that he has seen Donald Trump waiting for an elevator. Why Donald Trump? Was this supposed to be a joke related to some events or news of that time?

The dialogue:

Joey: Uh, so your weekend was a total bust?

Chandler: Uh, no, I got to see Donald Trump waiting for an elevator.

Joey: You know, at the Taj Mahal, he has his own private glass elevator. That's right. Made by Otis Elevators. Yeah. And they usually don't do glass.