My posts* got to the first spot on hackernews couple of times. Never once it broke down like that. And why would it, it's just a bunch of html and css files served through (free) vercel (don't think it matters). I wonder what do people run their blogs these days, so they fail under the pressure so easily.
Cheap shared hosting will throttle sites which get too much traffic.
It's WordPress, which is a great CMS but can quickly crumble under load when using cheap hosting.