The available information changed. This very quickly went from something many people weren't sure wasn't going to be maybe a nasty flu to something that has half the world staying home from work and hospitals getting overrun. Changing your procedures in response to new information is what managers should be doing.
They'd have been smarter to respond to it sooner, but better late than never.
You're trying to spin it both ways. If Amazon was just idiotic about their response to the outbreak, why did they pick that moment to suddenly take things super serious and fire the employee?