I have this pretty much and generating way too much power for our needs which is great. And that includes car charging for light but significant use. I export a lot during peak hours from the battery as there is a lot of surplus.
But I was snarking on "provider". There are 100s of providers where I live but one grid and you can't use two concurrently.
My backup in the past has been a local library for internet and laptop power and everything else can wait.
This is all getting quite silly but really large sites with critical power needs (hospitals, factories, data centres, etc) will sometimes have two independent grid supplies running in from separate substations, preferably going as far back down the chain as possible before hitting a single point of failure. They'll also have UPS and diesel generators able to kick in and keep things running if somehow they entirely lose grid power. Its all totally doable, but as you say for most people going to the local library or a coffee shop is a perfectly fine fallback plan.