Found a workaround if you are experiencing this issue when creating a new framework.
Open an earlier version of Xcode (I used Xcode 15.4.0).
Create your framework.
Add at least 1 .swift file to the framework in order to get the compiler settings to reveal.
Switch back to Xcode 16.2 and now you can see all compiler settings.
Topic:
Developer Tools & Services
SubTopic:
Xcode
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