[BUG] claude-sonnet-3.5 is better for coding tasks than 4x

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

Prove me wrong

What Should Happen?

Dont deprecate 3.5 or make it opensource

Error Messages/Logs

Steps to Reproduce

Spend 5 hours in 4.x debugging, or spend 10 minutes in 3.5 getting s* done

Claude Model

Other

Is this a regression?

Yes, this worked in a previous version

Last Working Version

_No response_

Claude Code Version

2.0.1

Platform

Anthropic API

Operating System

Ubuntu/Debian Linux

Terminal/Shell

Other

Additional Information

_No response_