Looks like they’re using “smol” servers; it crashed under a few hundred HN visits ;)
To be honest, that's kind of the point. When you're "webscale" you're inevitably at a level where you have to pay a lot of money just to keep the site up. Smolnet is supposed to be run from someone's basement.
This is true when thinking in centralised big-site terms but there are other ways to achieve a large reach, some of them already close to main-stream. Peertube [1] is an example of such, using a combination of Activitypub and peer to peer (here: bittorrent) to create a "web scale" platform without needing a lot of money. Does it work? A good question, Peertube itself certainly works fine but it would be an interesting test to see how far it actually scales.