It depends a lot on the mode of transportation. The Seattle employee referenced in the article may commute by ferry, which is about as relaxing of a commute as possible. The Seattle ferries are very nice; you can sit in a booth and eat breakfast and read the newspaper. Here's a photo of what it looks like: https://www.nytimes.com/2012/04/01/travel/vashon-island-near.... I'd totally be willing to do that for an hour every morning and evening.

But would you do it for 4?

I thought when people said they had an X hour commute they typically meant that they traveled for X hours to work and X hours from work

Good point. Where I am, people usually use "X hour commute" to mean the full amount in a day.

I wonder what percentage of people interpret it to mean one way vs. both ways.

Yeah I was wondering to what degree it is a regional thing. I'm from Australia and most people seem to mean it one way, but I've been wondering how many times I've misunderstood people online

We should probably assume that people commute via car unless noted otherwise, since it is by far the most common method.

Generally speaking, I agree, but for three example locations that were given in the article, that's not the case. Google's offices tend to be in major cities, especially more liberal ones, and those often have good public transit. Both Seattle and NYC have more people who commute to the city center via public transit than by car; I'm not sure about the numbers for SF.

I agree 100% that 2 hour commutes are crappy, but a 2-hour commute on a nice form of public transit is very different than 2 hours of being stuck in traffic and stressed out.