Actually, I worked at DCA, National Airport, and the night Nixon resigned, the airport came to a complete standstill I'd never seen before or since. Planes at the gate did not board as passengers and crew watched Nixon's speech. At our ticket counter, all of the agents were in the break room directly in back of the ticket counter, also watching. We left the door open, just in case any passengers came up, but for at least fifteen minutes, not a single one showed. And this was a Friday night, typically the (by far) busiest day of the week.
I can also tell you that the day to day work of the government had come to nearly a complete standstill in the week or so before the resignation. No one knew for sure what would happen, and everything was in a holding pattern.
Even now, every time I see the resignation speech, I hold my breath, not convinced he's going to say, "I'm a fighter. I don't quit. And I'm remaining as your President."
In the end, he actually resigned with a certain amount of grace. Doubt that the Donald will do the same.