Not every person lives in San Francisco.
Not every engineer has the same skill level.
Not every team uses the hottest framework.
We can't build something only for the wealthy users but also for users at the margins (think the 90th percentile) who may not be on the fastest computers, wifi networks, or have access to the latest tech.
That's why we have a generous free tier.
That's why we have SDKs for all languages.
That's why we have docs for beginners.
That's why it must be fast.