Startup Minimal did not emerge from a design movement. It emerged from a single website: Stripe. Around 2015-2016, Stripe's marketing site established the template — white background, clean sans-serif type, gradient accents, developer-focused copy, and an air of quiet technical sophistication. The design was so effective at signaling "serious tech company" that it became the default.
Linear, Vercel, Raycast, and dozens of other developer-focused startups adopted and refined the look. Inter replaced system fonts. Indigo and purple replaced Stripe's original green gradients. Tailwind CSS made the palette and spacing system trivially reproducible, and suddenly every YC company's landing page looked identical. The "trusted by" logo bar became mandatory. The pill-shaped button became universal.
The aesthetic is now so dominant that deviating from it is itself a statement. Choosing a serif font or a colored background for your startup's homepage signals either supreme confidence or total naivety. Startup Minimal is the path of least resistance, and for most companies, that is exactly the right choice.