Sora 2 vs Veo 3.1 vs Seedance 2.0 in 2026 (Post-Shutdown)

Sora 2 vs Veo 3.1 vs Seedance 2.0 in 2026 — but the Sora app shut down April 26 and the API sunsets September 24. Here's what each model still wins, and how to migrate before September.