alt Hacker Newssure we can quibble over convenience, but it's an outage, and you have to make it work. Look at the testing for the Anker Solix S2000 they are getting 2+ days of regular refrigerator use , which is what people care about primarily .
What other option is easier or more affordable? A generator has to remain outside, so it needs panel connection ($$) , lots of extensions ( $, hassle), needs a generous fuel supply, and regular maintenance.
And plug-in solar is becoming legal in the usa. within 3 years everyone will be running these little things, and you'll come around.
Exactly zero plug in solutions should be outputing power during an outage, if designed correctly, because they will be backfeed out of the house and into a grid. Most legislation directly addresses this.
So you're back to getting a tranfer switch installed or lots of cords anyways.