Confusion Over Pricing of Claude Sonnet Models Explained

Can anyone help me understand why Claude Sonnet 4, 3.7 and 3.5 are all priced the same on their website (image below), yet Sonnet 4 costs many times more Clay credits than 3.5 (and actually seems to be twice as expensive when using the API for the same prompt?). Genuinely curious why this could be 🤔