What are you talking about? Tons of people run personal blogs/websites, with an enormous variety of hosting structures.
I call that working in practice. The fact that any individual self-hosted site could not survive a DDOS does not negate the fact that, well, the internet actually does exist.
Absolutely false. Find me a non-trivial blog or website (>10k unique visitors per month) self-hosted by someone non-technical that isn't centralized by Cloudflare or a website host.
Like I said: if your site is read-only and you self-host, you're vulnerable to DDoS. You'll avoid it if you aren't very famous and aren't randomly targeted, but you're still vulernable.
And if your site has any kinds of comments, forms, or "write" ability, then you absolutely can't self-host. You will be blown away by spam and hacking attempts.
The "tons" of people you're talking about don't exist. They're mostly on WordPress, Ghost, Substack, or something similar with custom domains, and the ones who aren't are still mostly hiding behind Cloudflare.
Read-only sites, like personal blogs, are easy to self-host but vulnerable to DDoS attacks if targeted.
Writeable sites, like anything with a form or message board, are now too expensive to run because of spammers and hacking bots.
We're now all paying rent to Cloudflare or Substack or whatever because you can't just be an isolated island on the open web anymore.