I live in the Dallas, Texas, area and this week experienced numerous power outages lasting from a few minutes to almost a day. A small UPS kept all my networking equipment running for several hours into the long duration outages, and a big APC Smart-UPS 1500 kept a small server (a Gigabyte Brix with no moving parts) running through the entire series of outages. And like you, we charged our mobile devices from a UPS.
For two nights we stayed with friends who never lost power. Before we left I connected a Wyze Cam to a UPS, pointed the camera at an area with a history of flooding, and turned on a light not connected to a UPS. By watching the camera from our friend's house I could tell when power failed because the light would be off, as well as see if a water leak began flooding the room. Fortunately we have, so far, found no leaks. Knowing when power returned and stayed on for over 8 hours helped us decide when to return home.
Obviously I consider UPS units essential for protecting critical equipment and for providing a source of power during extraordinary events.