Just because someone has a CS degree doesn't mean they actually know what they're doing.
Cloudflare's no longer the darling of HN, but they unquestionably have clever people who are excellent developers. Just maybe not excellent at web dev and cache invalidation by the sound of it.
I say this as someone who is autodidactic (self-taught) with regards to software engineering. I never stop learning, reading, experimenting and just gaining as much understanding over everything I touch as I can. My mind doesn't always work like most people. And my statements are not meant to be insulting, just my point of view from the outside...
In that, I feel that a lot of FAANG (whatever the correct/current conflation is) tend to rely on a lot of focus that tends to favor those with a formal education, and those closer to that education (less experienced outside school). In practice, my experience is that this will lead to an excess in "Enterprise Pattern" usage as well as unnecessary complexity which leads to an increased risk of error.
At one point I didn't have proper access to something, but instead of getting a message saying that, I got some generic 500 error.