It’s seriously disappointing that OpenAI seemed to have blindly followed Claude’s design patterns with this update. It is genuinely one of the biggest factors that makes me prefer using ChatGPT over Claude.
This needs to be a setting, not enforced.
However, thank you to @Balrog2000 above for a great solution. The alternative on Mac is CMD + Option + Shift + V (the standard shortcut for “Paste and Match style”)