There were also many video startups before YouTube, but the web wasn't ready for them (infrastructure, speed, etc.). Webvan was a long time ago and the failure

There were also many video startups before YouTube, but the web wasn't ready for them (infrastructure, speed, etc.). Webvan was a long time ago and the failure of it is well-documented in Four Steps to the Epiphany, which said they built before reaching product market fit. Now I don't know much about Instacart, so I can't speak to how they're doing, but that doesn't mean the world isn't ready for this generation's Webvan.