Most people just deal with it and accept that their site will go down for 20 minutes every 3-4 years or so, even when hosting on a major cloud, because:

1) the cost of mitigating that risk is much higher than the cost of just eating the outage, and

2) their high traffic production site is routinely down for that long anyway, for unrelated reasons.

If you really, really can't bear the business costs of an entire provider ever going down, even that rarely (e.g. you're doing life support, military systems, big finance), then you just pay a lot of money to rework your entire system into a fully redundant infrastructure that runs on multiple providers simultaneously.

There really aren't any other options besides these two.