Have you ever self hosted a website? Was that a modern website, or just a bunch of text? Are you experienced with uptime SLAs on multiple services? Have you ever had to deal with a DDOS attack?
There are lots of things that Cloudflare does that requires experience and knowledge to notice or understand. And it isn't even the biggest single point of failure when it comes to the Internet. When AWS has an outage for instance there is a huge chunk of the Internet that goes down.
There are problems with the centralization of the Internet. But this happened for a reason, and it has been so long and these services have been so reliable that people don't even realize what it was like before.