My Samsung got the notification from Google too, so probably not a Pixel exclusive thing.
Though I wish it would have overridden silent mode. 10s of advanced warning isn't all that helpful if I only find out about the notification 10 minutes later.
You just reminded me to go into my notification history and turn on "Override Do Not Disturb" for the earthquake early warning notification. I really like the notification history for that; you can go back to a notification you dismissed hours ago and edit its settings.
Was this under the "Crisis Alerts" category for Google? Going to set it for my phone too, even though this kind of thing really should be set to override do not disturb by default.
Apparently my phone supports notification history, but it was also turned off by default... Bad defaults strikes twice in a row.
Though I wish it would have overridden silent mode. 10s of advanced warning isn't all that helpful if I only find out about the notification 10 minutes later.