> You've just witnessed almost the entire internet break because of a catastrophic cascading outage that affected lots of huge companies, since third party services used and trusted Fastly.

Blame the companies that relied on Fastly being up 100% of the time, even though Fastly explicitly states that they might be down any number of hours, and they will even give you money back for that [1]. If they did offer 100% SLA, it would probably be out of budget for most users, as that kind of systems are prohibitively expensive to run.

Depending on a single CDN like Fastly is building an SPOF into your product. It is not less of a design blunder that whatever Fastly did internally to have an outage. If Shopify lost millions because of a short, simple third-party outage they have at least as much of a high-priority postmortem to write and issues to address as Fastly.

[1] - https://docs.fastly.com/products/service-availability-sla