I've witnessed this myself. In 2009 the company I was working for in Calabasas, California, laid off a lot of people. Since I rented, I was able to end my lease and move to a new job in Orange County. Colleagues who had bought and were underwater were forced to search for new jobs within commuting distance of their house.

Same here! Was living in NE during the 2007 crisis. Found a new job, gave my landlord 30 days and done.

I had coworkers who wanted to find a new but were now $200K under on their house.

The mobility renting offers can't be understated.

Why?

I think they're saying renters can move without taking a large loss, but owners generally can't, since they have to either sell at a loss, or rent out their property at a loss.

Negative equity. £200k mortgage on a house now worth £150k. To move, first find £50k.

You can just leave the house empty without selling it.

You just need to pay taxes and mortgage but not utilities for your empty house.

That can work for some. Paying a mortgage and rent on the new location, along with 2 sets of taxes gets expensive real quick. Some utilities have standing charges/line rental too.