The state of the art models (mostly GPT 5.5, but also Gemini and Claude) are better so they cost more. Qwen 3.7 Max is their only direct competition and it is not any cheaper.
I have been using DeepSeek, and I am finding it better than Claude or Codex, to be honest.
I don't see myself going back.
that being said, deepseek v4 needs to be on amazon bedrock to actually be feasible in the US Enterprise market and start driving other provider prices down