@Gwen386 well, nobody knows if it was an emergency until @Ashley1433 figures out what house rule she broke, right? So there is no point in calling Airbnb now.
Everyone is concentrated on the reaction/consequence (the host entered the premises) instead of the action/the cause ( Ashley broke the unknown house rule).
Yes, theoretically, the host should have contacted the guest first except if there is an emergency. From my experience, guests rarely have Airbnb app and get notifications. I usually have to wait a few hours or a few days before my guest responds. Even Whatsapp messages are rarely answered immediately.
So, if, for example, the guest left the doors unlocked, windows open, and A/C running it is understandable why the host entered (to protect his property, the guest's possessions and stop over-consumption in the middle of the energy crises). There must be a good reason, otherwise, if the host just wanted to snoop around he wouldn't leave a message.
There are always 2 sides of the story.