Their business is making big complicated things possible for companies that are going to spend a lot of money and don't care about a small amount of incidental complexity.
While imposing technical limitations to extract more revenue along the way.
I dislike the UX of AWS but the complexity here isn't strange to me. I bothered to set up the first bit of this (didn't need sub-dir index files so didn't realize it was a problem) since I wanted a simple storage, simple deploy and good resilience.
My site has been hit by HN a few times now and it hasn't been an issue. Fairly set and forget. But the start is annoying.
Only costs ~$27/year to have a domain($15) and a static website deployed to S3/R53 ($1/month), which I've found to be fairly reasonable for the level of reliability I can expect.
I admit it is complicated up front but once it is setup and updates are automated it is really nice to not need to worry about self hosting, hardware, VPS', etc just for a simple website.
Or create an organisation on Github and publish this website as a Page. It is simple and it is free.
https://help.github.com/en/github/working-with-github-pages/...
Edit: I see others mentioned this too, but hopefully the link adds some added benefit!