It seems like you might need less output tokens for the same quality of response though. One of their plots shows o3 needing ~14k tokens to get 69% on SWE-bench Verified, but GPT-5 needing only ~4k.
O3 has had some major price cuts since Gemini 2.5 Pro came out. At the time, o3 cost $10/Mtok in and $40/Mtok out. The big deal with Gemini 2.5 Pro was it had comparable quality to o3 at a fraction of the cost.
I'm not sure when they slashed the o3 pricing, but the GPT-5 pricing looks like they set it to be identical to Gemini 2.5 Pro.
GPT-5 pricing: $10/Mtok out
What am I missing?