If they don't come it and don't resign themselves, then I assume google would fire them in which case they would get severance? Is that how it works? It's only an issue if the people who wfh resign then they would not get severance/unemployment?

In the case of not coming in it’s kind of a gray area right now. Some stipulate failing to come to the office would be a failure to perform and so the employee would be fired without severance but still be able to collect unemployment.

People who resign would be quitting on their own accord and would not be able to receive neither a severance nor unemployment. That’s why resignations are probably Google’s ultimate goal.

I'm sure that everyone that Google would fire because of this would receive at least the severance prescribed by law: nothing.