If you live in NoCA with PG&E and the frequent Public Safety Power Shutoffs (at every possible wildfire or storm), then you experience outages with your ISP. Mine is Comcast. The Gigabit speed is great when up, but when down, I am dead in the water with no internet access (...very bad cell coverage at my home, where I use WiFi calling). Even though I have Powerwalls, the Comcast network relies on hubs and nodes that need power. If my neighborhood is under a PSPS, then Comcast goers down in a couple of hours. Oh, and I do have Xfinity/Comcast video and VoIP phone lines.
So I got HughesNet satellite internet as a backup. Sort of like the restaurant where 'not only is the food bad, but the portions are small'. Slow service (like 25 Megs down), bandwidth cap (like 5 Gig per month), and pricey (like$80/month). So I can't wait to tear the big ugly HughesNet dish off of my roof and use Starlink as a real backup.
Do cell tower also go down? We have shut off here in SoCal too, but our backup is T-Mobile hotspot. It's 80Mbps down and 20Mbps up free 20GB per month per line. Cell service doesn't seem to go down here. I think they have their own backup generators for safety purposes.