Constraints: App will be served on the app store
You may need to re-check the App Review Guidelines, especially this part:
2.5 Software Requirements - https://developer.apple.com/app-store/review/guidelines/#software-requirements.2 Apps should be self-contained in their bundles, and may not read or write data outside the designated container area, nor may they download, install, or execute code which introduces or changes features or functionality of the app, including other apps. Educational apps designed to teach, develop, or allow students to test executable code may, in limited circumstances, download code provided that such code is not used for other purposes. Such apps must make the source code provided by the Application completely viewable and editable by the user.
Your app would be considered to be an educational app, but not designed to teach, develop, or allow students to test executable code.
So, download and run a swiftUI view file would never be approved whether it is in a source file or some sort of compiled binary.
If you can represent your packs in other format (for example, HTML & JavaScript), your app can be considered to be sort of packs player, and may have some chance to be approved. Sorry, just my opinion.