The short answer is "backwards compatibility". The long answer is... well, it's the rest of this video. MORE BASICS:    • The Basics   Written with Sean Elliott https://twitter.com/SeanMElliott/ Graphics by William Marler https://wmad.co.uk/ Audio mix by Graham Haerther https://haerther.net/ 🟥 MORE FROM TOM: https://www.tomscott.com/ (you can find contact details and social links there too) 📰 WEEKLY NEWSLETTER with good stuff from the rest of the internet: https://www.tomscott.com/newsletter/ ❓ LATERAL, free weekly podcast: https://lateralcast.com/ null ➕ TOM SCOTT PLUS: null 👥 THE TECHNICAL DIFFICULTIES: null