There’s no magic wand that produces good outcomes when planning or execution goes awry at scale.
Just because this isn't a good solution for everyone, doesn't mean it's not a good solution for a large number of people and businesses.
A lot of businesses can tolerate outages. In fact, even very big businesses come out mostly unscathed when they have multi-hour outages. (how many is it for github this year?)
An outage causes a reputational black eye. It does not necessarily translate to lost income.
If you're a big business that wants to spend unlimited money, you apply for unlimited credit with a credit check.
If you don't, you get hard caps.