Voice/chat agents on GPT-5.6 are running at roughly one-tenth the cost of GPT-4.1 while autonomously resolving up to 65% of inbound customer calls across multiple languages and channels. That cost collapse makes full voice deployment—not just text deflection—economically viable at scale, so if you've been gating agent rollouts on per-call inference spend, the math has fundamentally changed and the deflection ceiling is now high enough to displace significant human support headcount.