Ask HN: Not a webdev, why are these sites so good?

I've noticed many new websites, belonging mostly to startups, have got exceedingly 'good': they are concise, simple, and super super fast.

So really a two part question: 1. (Style) Maybe a new shared design paradigm? 2. (Speed) These sites load so fast on my machine, as if Chrome is preloading them, or is it just that like Vercel / Netlify / whatever else has gotten really good?

Examples (that I can remember): https://cleanlab.ai/ https://diracinc.com/ https://elevenlabs.io/