It’s just a function of costs vs benefits. For most people, building redundancy at this layer costs far too much than the benefits.

If Cloudflare or AWS go down, the outage is usually so big that smaller players have an excuse and people accept that.

It’s as simple as that.

“Why isn’t your site working?” “Half the internet is down, here read this news article: …” “Oh, okay, let me know when it’s back!”