The problem is the blackouts can go for lengths of time that would require impractically large battery installs. You can powerwall your way around a grid that frequently goes down for a few hours to a day, but one that may go down for days to months you are practically forced into some form of generation (solar or otherwise).

Batteries keep getting cheaper but are unlikely to get to where it’s more affordable to store a month’s worth of electricity than just buying some generation.