Businesses? I'm thinking it's something a team of developers would use. There are a ton of project on GitHub that uses various CI/CD tools to build package, rather than letting a random developer build an distribute a new release. Similarly a company might want to use this to test, build and release software. Checking that patches and updates from any number of developers can be merged and verify that all tests still passes.

If I understand it correctly, it would also mean that use Xcode Cloud to release an application into the App Store. Then no single developer needs access to submit new versions.

Say you have a 6 or more developer team working on an app. Do you really want everyone to be able to create production builds? Or do you really want to rely on one guy having the production certificates?

What if you've outsourced your app development; do you really want random developers spread across the world from having the ability to make production builds?

Anyway, there's more authorative sources on the internet about "why CI" than some guy (me) in a comment section.