I worked at a company that's bread and butter was online services (e-commerce SaaS platform, similar to Netsuite) and we had significantly fewer outages than AWS had.

But we had redundancies built in to most things, I'm not saying it was perfect but it worked.

The major difference might be that almost nobody is willing to spend 20% of what they spend on AWS/GCP to have a self-hosted solution.

The reason "cloud is so expensive" is because they're essentially telling you what the price will be and even if they only spend 40% of that on actual hardware and operations: it's more than most companies would invest in themselves.

This is absurd, of course, but it's absolutely true.