Stablecoins in 2026: $300B in Supply, 1% Real Payments, and Rails Being Rebuilt for Agents

GENIUS Act rules are still proposals, Visa settles $7B a year in USDC, Stripe launched its own chain, and x402 has 165 million transactions worth about $50 million. An infrastructure engineer separates the settlement layer that is real from the agent-payments layer that is mostly still a demo.